platform,target: mdm9640: support glink for sdxhedgehog target

On sdxhedgehog, enabling glink to communicate with RPM.

Change-Id: I200b9dde8c8b0bbfeef6361bd991cbd336efd964
diff --git a/project/mdm9640.mk b/project/mdm9640.mk
index d72ee16..997f92c 100644
--- a/project/mdm9640.mk
+++ b/project/mdm9640.mk
@@ -50,6 +50,11 @@
 DEFINES += SMD_SUPPORT=1
 endif
 
+ENABLE_GLINK_SUPPORT := 1
+ifeq ($(ENABLE_GLINK_SUPPORT),1)
+DEFINES += GLINK_SUPPORT=1
+endif
+
 # Reset USB clock from target code
 DEFINES += USB_RESET_FROM_CLK=1