File reveng-obey-cflags.patch of Package reveng

diff --git a/Makefile b/Makefile
index 761612c..0925d85 100755
--- a/Makefile
+++ b/Makefile
@@ -23,7 +23,7 @@
 
 # C compiler and flags.  Adjust to taste.
 CC = gcc
-CFLAGS = -O3 -Wall -ansi -fomit-frame-pointer
+CFLAGS += -O3 -Wall -ansi -fomit-frame-pointer
 # Binary optimiser
 STRIP = strip
 SFLAGS = --strip-unneeded