geneve: constify geneve_hlen()

Such helper does not modify the argument; constifying it will additionally
simplify later patches.

Additionally move the definition earlier, still for later's patchesi sake.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Link: https://patch.msgid.link/ea9e279b9544e8644194508dd9a4320ee455fa95.1769011015.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Paolo Abeni 2026-01-21 17:11:31 +01:00 • committed by Jakub Kicinski
commit 759b8d3cef