mx7: Add 1.2GHz speed grade entry

There are recent MX7 parts that have a 1.2GHz speed grade.

Add support for it.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
diff --git a/arch/arm/cpu/armv7/mx7/soc.c b/arch/arm/cpu/armv7/mx7/soc.c
index 8cde77b..8422f24 100644
--- a/arch/arm/cpu/armv7/mx7/soc.c
+++ b/arch/arm/cpu/armv7/mx7/soc.c
@@ -105,6 +105,7 @@
 #define OCOTP_TESTER3_SPEED_800MHZ	0
 #define OCOTP_TESTER3_SPEED_500MHZ	1
 #define OCOTP_TESTER3_SPEED_1GHZ	2
+#define OCOTP_TESTER3_SPEED_1P2GHZ	3
 
 u32 get_cpu_speed_grade_hz(void)
 {
@@ -125,6 +126,8 @@
 		return 500000000;
 	case OCOTP_TESTER3_SPEED_1GHZ:
 		return 1000000000;
+	case OCOTP_TESTER3_SPEED_1P2GHZ:
+		return 1200000000;
 	}
 	return 0;
 }