Make sendfirm_win.c compile and work


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@17938 a1c6a512-1295-4272-9138-f99709370657
diff --git a/utils/MTP/Makefile b/utils/MTP/Makefile
index 63e7b3a..9cbacd8 100644
--- a/utils/MTP/Makefile
+++ b/utils/MTP/Makefile
@@ -8,7 +8,7 @@
 	gcc $(CFLAGS) $(LIBS) -o $(OUTPUT) sendfirm.c
 
 $(OUTPUT).exe: sendfirm_win.c
-	gcc $(CFLAGS) -o $(OUTPUT).exe sendfirm_win.c MTP_DLL.dll
+	mingw32-gcc $(CFLAGS) -o $(OUTPUT).exe sendfirm_win.c MTP_DLL.dll
 
 clean:
 	rm -f $(OUTPUT)