[srp] Fix SRP buffer sizes

[Damian-Nordic]

Problem

The code for calculating buffer sizes used for SRP service data wrongly assumed that commissionable services are used
only when the extended discovery is enabled. This wasn't caught before because the extended discovery was enabled by
default on all Thread platforms (until recently).

Change overview

Always assume a commissionable node service can be advertised.

Testing

Tested using nRF Connect example with the extended discovery disabled.

[github-actions]

PR #18139: Size comparison from 42bd156 to de2bdf8

Full report (20 builds for cc13x2_26x2, cyw30739, esp32, k32w, linux, mbed, nrfconnect, p6, telink)

platform	target	config	section	42bd1566	de2bdf8	change	% change
cc13x2_26x2	all-clusters-app	LP_CC2652R7	(read only)	690947	690947	0	0.0
			(read/write)	161404	161404	0	0.0
			.bss	75332	75332	0	0.0
			.data	3412	3412	0	0.0
			.rodata	102979	102979	0	0.0
			.text	587484	587484	0	0.0
	lock-ftd	LP_CC2652R7	(read only)	678503	678503	0	0.0
			(read/write)	164952	164952	0	0.0
			.bss	73492	73492	0	0.0
			.data	3236	3236	0	0.0
			.rodata	94767	94767	0	0.0
			.text	583256	583256	0	0.0
	lock-mtd	LP_CC2652R7	(read only)	627255	627255	0	0.0
			(read/write)	146308	146308	0	0.0
			.bss	69212	69212	0	0.0
			.data	3236	3236	0	0.0
			.rodata	94647	94647	0	0.0
			.text	532120	532120	0	0.0
	pump-app	LP_CC2652R7	(read only)	663051	663051	0	0.0
			(read/write)	181692	181692	0	0.0
			.bss	73756	73756	0	0.0
			.data	3268	3268	0	0.0
			.rodata	80971	80971	0	0.0
			.text	581596	581596	0	0.0
	pump-controller-app	LP_CC2652R7	(read only)	655943	655943	0	0.0
			(read/write)	188600	188600	0	0.0
			.bss	73812	73812	0	0.0
			.data	3232	3232	0	0.0
			.rodata	83911	83911	0	0.0
			.text	571548	571548	0	0.0
cyw30739	light	cyw930739m2evb_01	(read/write)	627594	627594	0	0.0
			.app_xip_area	530184	530184	0	0.0
			.bss	80052	80052	0	0.0
			.data	708	708	0	0.0
			.rodata	0	0	0	0.0
			.text	0	0	0	0.0
	lock	cyw930739m2evb_01	(read/write)	626482	626482	0	0.0
			.app_xip_area	530528	530528	0	0.0
			.bss	78628	78628	0	0.0
			.data	672	672	0	0.0
			.rodata	0	0	0	0.0
			.text	0	0	0	0.0
	ota-requestor-no-progress-logging	cyw930739m2evb_01	(read/write)	575242	575242	0	0.0
			.app_xip_area	469572	469572	0	0.0
			.bss	88048	88048	0	0.0
			.data	584	584	0	0.0
			.rodata	0	0	0	0.0
			.text	112	112	0	0.0
esp32	all-clusters-app	c3devkit	(read only)	1001096	1001096	0	0.0
			(read/write)	1475658	1475658	0	0.0
			.dram0.bss	68464	68464	0	0.0
			.dram0.data	14444	14444	0	0.0
			.flash.rodata	208304	208304	0	0.0
			.flash.text	1001096	1001096	0	0.0
			.iram0.text	62020	62020	0	0.0
		m5stack	(read only)	1056047	1056047	0	0.0
			(read/write)	478080	478080	0	0.0
			.dram0.bss	73984	73984	0	0.0
			.dram0.data	34184	34184	0	0.0
			.flash.rodata	238076	238076	0	0.0
			.flash.text	1050663	1050663	0	0.0
			.iram0.text	123107	123107	0	0.0
k32w	light	k32w061+release	(read/write)	685136	685136	0	0.0
			.bss	81248	81248	0	0.0
			.data	2020	2020	0	0.0
			.text	600164	600164	0	0.0
	lock	k32w061+release	(read/write)	730484	730484	0	0.0
			.bss	81680	81680	0	0.0
			.data	1980	1980	0	0.0
			.text	645120	645120	0	0.0
linux	chip-tool-no-interactive-ipv6only	arm64	(read only)	8844468	8844468	0	0.0
			(read/write)	643137	643137	0	0.0
			.bss	41105	41105	0	0.0
			.data	1192	1192	0	0.0
			.data.rel.ro	582048	582048	0	0.0
			.dynamic	560	560	0	0.0
			.got	14976	14976	0	0.0
			.init	24	24	0	0.0
			.init_array	184	184	0	0.0
			.rodata	432404	432404	0	0.0
			.text	6952756	6952756	0	0.0
	thermostat-no-ble	arm64	(read only)	2368620	2368620	0	0.0
			(read/write)	175121	175121	0	0.0
			.bss	86417	86417	0	0.0
			.data	1520	1520	0	0.0
			.data.rel.ro	79376	79376	0	0.0
			.dynamic	560	560	0	0.0
			.got	4768	4768	0	0.0
			.init	24	24	0	0.0
			.init_array	376	376	0	0.0
			.rodata	146844	146844	0	0.0
			.text	1992032	1992032	0	0.0
mbed	lock-app	CY8CPROTO_062_4343W+release	(read only)	6224	6224	0	0.0
			(read/write)	2420076	2420076	0	0.0
			.bss	205820	205820	0	0.0
			.data	5872	5872	0	0.0
			.text	1382676	1382676	0	0.0
nrfconnect	all-clusters-app	nrf52840dk_nrf52840	(read/write)	1179787	1179787	0	0.0
			bss	139680	139680	0	0.0
			rodata	151532	151532	0	0.0
			text	809860	809860	0	0.0
p6	all-clusters-app	default	(read/write)	2531536	2531536	0	0.0
			.bss	139328	139328	0	0.0
			.data	2808	2808	0	0.0
			.text	1489800	1489800	0	0.0
	light-app	default	(read/write)	2421592	2421592	0	0.0
			.bss	132656	132656	0	0.0
			.data	2608	2608	0	0.0
			.text	1379856	1379856	0	0.0
	lock-app	default	(read/write)	2431096	2431096	0	0.0
			.bss	132472	132472	0	0.0
			.data	2568	2568	0	0.0
			.text	1389360	1389360	0	0.0
telink	lighting-app	tlsr9518adk80d	(read/write)	806024	806024	0	0.0
			bss	72176	72176	0	0.0
			noinit	40416	40416	0	0.0
			text	572432	572432	0	0.0

[andy31415]

/rebase