hooks/script-wrapper: multiple run protection.

common/hooks/pre-configure/02-script-wrapper.sh

@@ -81,6 +81,7 @@ _EOF
 
 hook() {
 	[ -z "$CROSS_BUILD" ] && return 0
+	[ -e "$XBPS_WRAPPERDIR/done" ] && return 0
 
 	# create wrapers
 	pkgconfig_wrapper
@@ -110,5 +111,6 @@ hook() {
 	python_wrapper python-config 2.7
 	python_wrapper python3.4-config 3.4m
 
+	touch $XBPS_WRAPPERDIR/done
 	export PATH="$XBPS_WRAPPERDIR:$PATH"
 }