ARM: OMAP2+: AM43x: resolve SMP related build error

If AM43x and SMP is selected, OMAP4 & OMAP5 deselected, build error as
follows,

arch/arm/mach-omap2/built-in.o: In function `scu_gp_set':
arch/arm/mach-omap2/sleep44xx.S:131: undefined reference to `omap4_get_scu_base'
arch/arm/mach-omap2/sleep44xx.S:132: undefined reference to `scu_power_mode'
arch/arm/mach-omap2/built-in.o: In function `scu_gp_clear':
arch/arm/mach-omap2/sleep44xx.S:227: undefined reference to `omap4_get_scu_base'
arch/arm/mach-omap2/sleep44xx.S:229: undefined reference to `scu_power_mode'

Resolve it by building sleep44xx.S only for OMAP4 & OMAP5.
Signed-off-by: NAfzal Mohammed <afzal@ti.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

arch/arm/mach-omap2/Makefile

@@ -35,10 +35,9 @@ obj-$(CONFIG_SOC_HAS_OMAP2_SDRC)	+= sdrc.o
 
 smp-$(CONFIG_SMP)			+= omap-smp.o omap-headsmp.o
 smp-$(CONFIG_HOTPLUG_CPU)		+= omap-hotplug.o
-omap-4-5-common				=  omap4-common.o omap-wakeupgen.o \
-					   sleep44xx.o
-obj-$(CONFIG_ARCH_OMAP4)		+= $(omap-4-5-common) $(smp-y)
-obj-$(CONFIG_SOC_OMAP5)			+= $(omap-4-5-common) $(smp-y)
+omap-4-5-common				=  omap4-common.o omap-wakeupgen.o
+obj-$(CONFIG_ARCH_OMAP4)		+= $(omap-4-5-common) $(smp-y) sleep44xx.o
+obj-$(CONFIG_SOC_OMAP5)			+= $(omap-4-5-common) $(smp-y) sleep44xx.o
 obj-$(CONFIG_SOC_AM43XX)		+= $(omap-4-5-common)
 
 plus_sec := $(call as-instr,.arch_extension sec,+sec)