ARM: imx: add initial imx6dl support

The i.MX6 DualLite/Solo is another i.MX6 family SoC, which is highly
compatible with i.MX6 Quad/Dual.  And that's why we choose to support
it using imx6q code with cpu_is_imx6dl() check when necessary.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index 5b676d4..2b09a04 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -790,7 +790,7 @@
 	  This enables support for Freescale i.MX53 processor.
 
 config SOC_IMX6Q
-	bool "i.MX6 Quad support"
+	bool "i.MX6 Quad/DualLite support"
 	select ARCH_HAS_CPUFREQ
 	select ARCH_HAS_OPP
 	select ARM_CPU_SUSPEND if PM