omap2plus: omap4: Set NR_CPU to 2 instead of default 4

The omap2plus_defconfig picks default NR_CPU value as 4 which isn't
correct for OMAP4430. Available CPUs are ony 2, so fix the same.
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/configs/omap2plus_defconfig

@@ -58,6 +58,7 @@ CONFIG_ARM_ERRATA_411920=y
 CONFIG_NO_HZ=y
 CONFIG_HIGH_RES_TIMERS=y
 CONFIG_SMP=y
+CONFIG_NR_CPUS=2
 # CONFIG_LOCAL_TIMERS is not set
 CONFIG_AEABI=y
 CONFIG_LEDS=y