Merge branch 'flexible-array-for-ip-tunnel-options'

Gal Pressman says:

====================
Flexible array for ip tunnel options

Remove the hidden assumption that options are allocated at the end of
the struct, and teach the compiler about them using a flexible array.

First patch is converting hard-coded 'info + 1' to use ip_tunnel_info()
helper.
Second patch adds the 'options' flexible array and changes the helper to
use it.

v4: https://lore.kernel.org/20250217202503.265318-1-gal@nvidia.com
v3: https://lore.kernel.org/20250212140953.107533-1-gal@nvidia.com
v2: https://lore.kernel.org/20250209101853.15828-1-gal@nvidia.com
====================

Link: https://patch.msgid.link/20250219143256.370277-1-gal@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>