buildgcc: defer cleaning up the tree a bit

cleanup() uses BUILDDIRPREFIX, which is set after the
getopt loop.

Change-Id: I8a904781ee4fefc42681d31e94b64008cf03750a
Signed-off-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-on: http://review.coreboot.org/4544
Tested-by: build bot (Jenkins)
Reviewed-by: Jonathan A. Kollasch <jakllsch@kollasch.net>
diff --git a/util/crossgcc/buildgcc b/util/crossgcc/buildgcc
index 5d7ac6f..87054f2 100755
--- a/util/crossgcc/buildgcc
+++ b/util/crossgcc/buildgcc
@@ -208,7 +208,7 @@
         case "$1" in
 		-V|--version)	shift; myversion; exit 0;;
 		-h|--help)	shift; myhelp; exit 0;;
-		-c|--clean)	shift; cleanup;;
+		-c|--clean)	shift; clean=1;;
 		-t|--savetemps)	shift; SAVETEMPS=1;;
 		-d|--directory)	shift; TARGETDIR="$1"; shift;;
 		-p|--platform)	shift; TARGETARCH="$1"; shift;;
@@ -235,6 +235,10 @@
 echo "Target arch is now $TARGETARCH"
 BUILDDIRPREFIX=build-${TARGETARCH}
 
+if [ "$clean" = "1" ]; then
+	cleanup
+fi
+
 GDB_PACKAGE="GDB"
 PYTHON_PACKAGE="PYTHON"
 EXPAT_PACKAGE="EXPAT"