apparmor: lift new_profile declaration to remove C23 extension warning

apparmor: lift new_profile declaration to remove C23 extension warning

the kernel test robot reports a C23 extension
warning: label followed by a declaration is a C23 extension
[-Wc23-extensions]
     696 |                 struct aa_profile *new_profile = NULL;

Instead of adding a null statement creating a C99 style inline var
declaration lift the label declaration out of the block so that it no
longer immediatedly follows the label.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202411101808.AI8YG6cs-lkp@intel.com/
Fixes: ee650b3820f3 ("apparmor: properly handle cx/px lookup failure for complain")
Signed-off-by: John Johansen <john.johansen@canonical.com>