imx: add i.MX6ULZ cpu type

Add i.MX6ULZ cpu type and helper.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Ye Li <ye.li@nxp.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
diff --git a/arch/arm/mach-imx/mx6/soc.c b/arch/arm/mach-imx/mx6/soc.c
index 075d246..d37d385 100644
--- a/arch/arm/mach-imx/mx6/soc.c
+++ b/arch/arm/mach-imx/mx6/soc.c
@@ -85,6 +85,10 @@
 				type = MXC_CPU_MX6D;
 		}
 
+		if (type == MXC_CPU_MX6ULL) {
+			if (readl(SRC_BASE_ADDR + 0x1c) & (1 << 6))
+				type = MXC_CPU_MX6ULZ;
+		}
 	}
 	major = ((reg >> 8) & 0xff);
 	if ((major >= 1) &&