fs/kernfs/symlink.c: replace S_IRWXUGO with 0777 on kernfs_create_link()

fs/kernfs/symlink.c: replace S_IRWXUGO with 0777 on kernfs_create_link()

If one ends up extending this line checkpatch will complain about the
use of S_IRWXUGO suggesting it is not preferred and that 0777
should be used instead. Take the tip from checkpatch and do that
change before we do our subsequent changes.

This makes no functional changes.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20210927163805.808907-8-mcgrof@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>