ARM: brcmstb: Kconfig: drop unneeded symbol selections

These are either implied or not necessary.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

arch/arm/mach-bcm/Kconfig

@@ -118,10 +118,7 @@ config ARCH_BCM_63XX
 
 config ARCH_BRCMSTB
 	bool "Broadcom BCM7XXX based boards" if ARCH_MULTI_V7
-	depends on MMU
 	select ARM_GIC
-	select MIGHT_HAVE_PCI
-	select HAVE_SMP
 	select HAVE_ARM_ARCH_TIMER
 	select BRCMSTB_GISB_ARB
 	select BRCMSTB_L2_IRQ