Add API:mbtk_get_modem_version from v2.

Change-Id: I5df09ddfaf0b7d55822e1b0b559b014a36bfdc48
diff --git a/mbtk/libmbtk_lib/ril/v2/ril_utils.c b/mbtk/libmbtk_lib/ril/v2/ril_utils.c
index b3f3fdd..33b25a8 100755
--- a/mbtk/libmbtk_lib/ril/v2/ril_utils.c
+++ b/mbtk/libmbtk_lib/ril/v2/ril_utils.c
@@ -226,7 +226,8 @@
         case RIL_MSG_ID_DEV_POWERIND:
             return "POWERIND";
         // Sim Information
-
+        case RIL_MSG_ID_DEV_MD_VERSION_REQ:
+            return "MD_VERSION";
         // <uint8> 0:NOT_EXIST 1:READY ...
         case RIL_MSG_ID_SIM_STATE:
             return "SIM_STATE";