msm: iommu: Kconfig item for cacheable page tables

Add a Kconfig item to allow the IOMMU page tables to be
coherent in the L2 cache. This generally reduces IOTLB miss
latencies and has been shown to improve multimedia
performance.
Signed-off-by: NStepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: NDaniel Walker <dwalker@codeaurora.org>

arch/arm/mach-msm/Kconfig

@@ -122,6 +122,10 @@ config MACH_MSM8X60_FFA
 
 endmenu
 
+config IOMMU_PGTABLES_L2
+	def_bool y
+	depends on ARCH_MSM8X60 && MMU && SMP && CPU_DCACHE_DISABLE=n
+
 config MSM_DEBUG_UART
 	int
 	default 1 if MSM_DEBUG_UART1