openrisc: fix CONFIG_UID16 setting

openrisc-allnoconfig:

  kernel/uid16.c: In function 'SYSC_setgroups16':
  kernel/uid16.c:184:2: error: implicit declaration of function 'groups_alloc'
  kernel/uid16.c:184:13: warning: assignment makes pointer from integer without a cast

openrisc shouldn't be setting CONFIG_UID16 when CONFIG_MULTIUSER=n.

Fixes: 2813893f ("kernel: conditionally support non-root users, groups and capabilities")
Reported-by: Fengguang Wu <fengguang.wu@gmail.com>
Cc: Iulia Manda <iulia.manda21@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/openrisc/Kconfig

@@ -17,6 +17,7 @@ config OPENRISC
 	select GENERIC_IRQ_SHOW
 	select GENERIC_IOMAP
 	select GENERIC_CPU_DEVICES
+	select HAVE_UID16
 	select GENERIC_ATOMIC64
 	select GENERIC_CLOCKEVENTS
 	select GENERIC_STRNCPY_FROM_USER
@@ -31,9 +32,6 @@ config MMU
 config HAVE_DMA_ATTRS
 	def_bool y
 
-config UID16
-	def_bool y
-
 config RWSEM_GENERIC_SPINLOCK
 	def_bool y