Don't set CFLAGS and LDFLAGS in makefile.
Use CFLAGS and LDFLAGS as set by debhelper and modified in debian/rules.

--- ./makefile.orig	2012-05-23 06:20:04.000000000 +0000
+++ ./makefile	2012-05-23 06:25:42.000000000 +0000
@@ -47,8 +47,6 @@
 CFLAGS = -MMD -g3 -O3 -march=$(MARCH) -Wall -pg
 LDFLAGS = `sdl-config --libs` -lSDL_image -lSDL_mixer -lGL -lGLU -pg
 else
-CFLAGS = -MMD -O3 -march=$(MARCH) -Wall $(SDL_FLAGS)
-LDFLAGS = `sdl-config --libs` -lSDL_image -lSDL_mixer -lGL -lGLU -s
 endif
 endif