build: allow GZIP to be set to empty string in configure.

configure

@@ -325,7 +325,7 @@ done
 HEADERS=${HEADERS:-"${PREFIX}/include"}
 LIBRARY=${LIBRARY:-"${PREFIX}/lib"}
 MANDIR=${MANDIR:-"${PREFIX}/share/man"}
-GZIP=${GZIP:-"gzip -c"}
+GZIP=${GZIP-"gzip -c"}
 POINTER_PACK_ENABLE=${POINTER_PACK_ENABLE:-"CK_MD_POINTER_PACK_DISABLE"}
 DISABLE_DOUBLE=${DISABLE_DOUBLE:-"CK_PR_ENABLE_DOUBLE"}
 PPC32_LWSYNC_ENABLE=${PPC32_LWSYNC_ENABLE:-"CK_MD_PPC32_LWSYNC_DISABLE"}
@@ -583,6 +583,7 @@ else
 	echo "success [$BUILD_DIR]"
 fi
 
+if test -n "$GZIP"; then
 	printf "Finding gzip tool................"
 	GZIP=`pathsearch "${GZIP:-gzip}"`
 	if test -z "$GZIP" -o ! -x "$GZIP"; then
@@ -592,13 +593,17 @@ fi
 
 	if test -z "$GZIP"; then
 		echo "not found"
-	GZIP=cat
-	GZIP_SUFFIX=""
 	else
 		echo "success [$GZIP]"
 		GZIP="$GZIP -c"
 		GZIP_SUFFIX=".gz"
 	fi
+fi
+
+if test -z "$GZIP"; then
+	GZIP=cat
+	GZIP_SUFFIX=""
+fi
 
 printf "Finding suitable compiler........"
 if test ! -x "${CC}"; then