project: mdm9625: Add support to override linker

Some target use ld.bfd linker instead of ld, override
the specific linker from project makefile.

CRs-Fixed: 626209
Change-Id: I8d816e8cf7f94d307c24017ccf7c201f67837fb1
diff --git a/project/mdm9625.mk b/project/mdm9625.mk
index 3f582bd..b9b72aa 100644
--- a/project/mdm9625.mk
+++ b/project/mdm9625.mk
@@ -15,3 +15,6 @@
 
 #disable Thumb mode for the codesourcery/arm-2011.03 toolchain
 ENABLE_THUMB := false
+
+#Override linker
+LD := $(TOOLCHAIN_PREFIX)ld.bfd