route-table: Use callback for handling route msgs. #6674

Job	Run time
libreswan (ubuntu-24.04)	4s
dpdk gcc (ubuntu-24.04)	5s
linux deb no dpdk	4m 56s
linux rpm fedora	4m 0s
build oss-fuzz fuzzers	2m 52s
osx clang --disable-ssl	1m 39s
clang-analyze-cache	10m 57s
linux gcc --disable-ssl	3m 24s
linux clang --disable-ssl	2m 35s
linux gcc c99	2m 39s
linux clang c99	2m 34s
linux gcc test	8m 30s
linux clang address,undefined test	16m 38s
linux gcc test --enable-shared	13m 21s
linux clang test --enable-shared	12m 10s
linux gcc check check-dpdk dpdk	19m 4s
linux clang check check-dpdk dpdk	18m 58s
linux gcc test -ljemalloc	9m 15s
linux clang test -ljemalloc	9m 27s
linux gcc --enable-afxdp	2m 39s
linux clang --enable-afxdp	2m 52s
linux gcc dpdk --enable-shared	3m 30s
linux clang dpdk --enable-shared	3m 35s
linux gcc dpdk-shared	3m 10s
linux clang dpdk-shared	3m 4s
linux gcc dpdk-shared --enable-shared	3m 45s
linux clang dpdk-shared --enable-shared	3m 44s
linux gcc m32 --disable-ssl	2m 32s
linux gcc check-ovsdb-cluster	6m 50s
linux gcc check-kernel -100	10m 40s
linux gcc check-kernel 100-	16m 59s
linux clang address,undefined check-kernel -100	13m 3s
linux clang address,undefined check-kernel 100-	19m 34s
linux gcc check-offloads -100	9m 32s
linux gcc check-offloads 100-	11m 55s
linux gcc dpdk check-system-userspace	12m 1s
linux clang address,undefined dpdk check-system-userspace	17m 57s
linux gcc dpdk check-system-tso	12m 12s
linux gcc dpdk check-afxdp	12m 10s
clang-analyze	10m 24s
	5h 25m 16s

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