route-table: Use callback for handling route msgs. #6628

Job	Run time
libreswan (ubuntu-24.04)	8s
linux rpm fedora	4m 4s
dpdk gcc (ubuntu-24.04)	6s
linux deb no dpdk	5m 25s
build oss-fuzz fuzzers	3m 2s
osx clang --disable-ssl	1m 29s
clang-analyze	20m 25s
linux gcc --disable-ssl	2m 45s
linux clang --disable-ssl	2m 41s
linux gcc c99	2m 51s
linux clang c99	2m 49s
linux gcc test	8m 20s
linux clang address,undefined test	16m 29s
linux gcc test --enable-shared	11m 23s
linux clang test --enable-shared	11m 24s
linux gcc check check-dpdk dpdk	18m 59s
linux clang check check-dpdk dpdk	18m 30s
linux gcc test -ljemalloc	9m 1s
linux clang test -ljemalloc	9m 1s
linux gcc --enable-afxdp	2m 51s
linux clang --enable-afxdp	2m 35s
linux gcc dpdk --enable-shared	3m 53s
linux clang dpdk --enable-shared	3m 50s
linux gcc dpdk-shared	3m 7s
linux clang dpdk-shared	3m 8s
linux gcc dpdk-shared --enable-shared	3m 53s
linux clang dpdk-shared --enable-shared	3m 40s
linux gcc m32 --disable-ssl	2m 48s
linux gcc check-ovsdb-cluster	6m 56s
linux gcc check-kernel -100	10m 55s
linux gcc check-kernel 100-	16m 3s
linux clang address,undefined check-kernel -100	25m 37s
linux clang address,undefined check-kernel 100-	30m 15s
linux gcc check-offloads -100	9m 58s
linux gcc check-offloads 100-	11m 45s
linux gcc dpdk check-system-userspace	12m 27s
linux clang address,undefined dpdk check-system-userspace	30m 15s
linux gcc dpdk check-system-tso	12m 31s
linux gcc dpdk check-afxdp	12m 13s
	5h 57m 32s

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