Merge branch 'ipv4-fib-convert-rtm_newroute-and-rtm_delroute-to-per-netns-rtnl'

Kuniyuki Iwashima says:

====================
ipv4: fib: Convert RTM_NEWROUTE and RTM_DELROUTE to per-netns RTNL.

Patch 1 is misc cleanup.
Patch 2 ~ 8 converts two fib_info hash tables to per-netns.
Patch 9 ~ 12 converts rtnl_lock() to rtnl_net_lcok().

v2: https://lore.kernel.org/20250226192556.21633-1-kuniyu@amazon.com
v1: https://lore.kernel.org/20250225182250.74650-1-kuniyu@amazon.com
====================

Link: https://patch.msgid.link/20250228042328.96624-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>