allow CC override
--- mISDNuser-1_1_9.orig/lib/Makefile	2008-11-18 12:35:09.000000000 +0100
+++ mISDNuser-1_1_9/lib/Makefile	2011-07-11 17:12:25.341001554 +0200
@@ -1,4 +1,4 @@
-CC = gcc
+CC ?= gcc
 AR = ar
 RANLIB = ranlib