trivial formatting fix for the config.mak generated by configure

(cherry picked from commit 7c6db373a55a348b3ecc7b124dd4ea541eff63cd)

configure

@@ -538,7 +538,7 @@ libdir = $libdir
 includedir = $includedir
 syslibdir = $syslibdir
 CC = $CC
-CFLAGS= $CFLAGS_AUTO $CFLAGS
+CFLAGS = $CFLAGS_AUTO $CFLAGS
 CFLAGS_C99FSE = $CFLAGS_C99FSE
 CFLAGS_MEMOPS = $CFLAGS_MEMOPS
 CPPFLAGS = $CPPFLAGS