[ARM] fix kernel-doc syntax

Fix kernel-doc notation to use correct syntax.  Even though this should be
moved to where the function is actually implemented...

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>