firmware/sys/shell_extended: Added stg commands functions and se_* fixes

[CW-75]

Contribution description

To use shell_extended storage commands, saves, loads, and deletes, only writing and reading an interface struct defined in #363 (This pr is merged with #363 and #362). implementing radio gets and sets, these functions allow you save set parameters in the mtd, and after read them, automatically, set that configuration in your own device.
Another little bugs were fixed from storage module, and shell_extended module

Testing procedure

Run the shell_extended example.

make -C examples/shell_extended flash term

• firs step command line testing (use ifconfig to set radio parameters {tx_power, channel} )

ifconfig [id radio interface] set power 4
ifconfig [id radio interface] set channel 20

• check your settings

> ifconfig
2022-10-13 19:48:21,456 # ifconfig
2022-10-13 19:48:21,463 # Iface  4  HWaddr: 4A:D4  Channel: 20  Page: 0  NID: 0x23  PHY: O-QPSK 
2022-10-13 19:48:21,464 #           
2022-10-13 19:48:21,469 #           Long HWaddr: 00:04:25:19:18:01:CA:D4 
2022-10-13 19:48:21,476 #            TX-Power: 4dBm  State: IDLE  max. Retrans.: 3  CSMA Retries: 4 
....

• Save them in the mtd_storage using stg save command.
• reset your device (Press device's reset button or using rebootcommand) .
• After reset use the stg load command to load all set parameters before.

expected output by the stg load

2022-10-13 19:48:25,264 # Netif_id: [radio interface id]
2022-10-13 19:48:25,266 # Type: Radio iface
2022-10-13 19:48:25,267 # id: [radio interface id]
2022-10-13 19:48:25,268 # Tx power 4
2022-10-13 19:48:25,269 # Channel: 20

• after that, check your current setting in your interfaces using ìfconfig, the expected output should be the same that step 2.

Also you can delete the interface register.

• write stg delin your shell
• check the register using stg load

expected output:

2022-10-13 19:47:12,808 # The register doesn't exists, first you need to save the interface info

Issues/PRs references

this depends of #362, #363

[CW-75]

After test the PR, will be removed the shell_commands of Makefile. only are used to ifconfig commands,

[luisan00]

looks good and works as expected, only a few conflicting files to fix and squashing before to merge 👍

[luisan00]

let's go ahead! 👍