selinux: ensure av_permissions.h is built when needed

stable inclusion
from stable-v5.10.180
commit 3ec77043a27d2dc7689cc570bfc9ba5015a76619
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8DDFN

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3ec77043a27d2dc7689cc570bfc9ba5015a76619



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[ Upstream commit 4ce1f694 ]

The Makefile rule responsible for building flask.h and
av_permissions.h only lists flask.h as a target which means that
av_permissions.h is only generated when flask.h needs to be
generated.  This patch fixes this by adding av_permissions.h as a
target to the rule.

Fixes: 8753f6be ("selinux: generate flask headers during kernel build")
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>