xfrm: extract dst lookup parameters into a struct

[ Upstream commit e509996b ]

Preparation for adding more fields to dst lookup functions without
changing their signatures.

Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Stable-dep-of: b8469721 ("xfrm: respect ip protocols rules criteria when performing dst lookups")
Signed-off-by: Sasha Levin <sashal@kernel.org>