ARM: 8359/1: correct secondary_startup_arm mode

secondary_startup_arm is used as ARM mode secondary start up function
when ther kernel is compiled in THUMB mode, however the label itself
is still in .thumb mode. readelf shows:

160979: c020a581   120 FUNC    GLOBAL DEFAULT    2 secondary_startup_arm

Make sure the label is in ARM mode as well.
Signed-off-by: NYingjoe Chen <yingjoe.chen@mediatek.com>
Tested-by: NMatthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/head.S

@@ -346,8 +346,8 @@ __turn_mmu_on_loc:
 
 #if defined(CONFIG_SMP)
 	.text
-ENTRY(secondary_startup_arm)
 	.arm
+ENTRY(secondary_startup_arm)
  THUMB(	adr	r9, BSYM(1f)	)	@ Kernel is entered in ARM.
  THUMB(	bx	r9		)	@ If this is a Thumb-2 kernel,
  THUMB(	.thumb			)	@ switch to Thumb now.