netfilter: uapi: Avoid undefined left-shift in xt_sctp.h

netfilter: uapi: Avoid undefined left-shift in xt_sctp.h

BugLink: https://bugs.launchpad.net/bugs/1861739
[ Upstream commit 164166558aacea01b99c8c8ffb710d930405ba69 ]

With 'bytes(__u32)' being 32, a left-shift of 31 may happen which is
undefined for the signed 32-bit value 1. Avoid this by declaring 1 as
unsigned.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>