abuild: set umask

consistent result regardless of current setting

abuild.in

@@ -30,6 +30,8 @@ BUILD_BASE="build-base"
 
 apk_opt_wait="--wait 30"
 
+umask 022
+
 # run optional log command for remote logging
 logcmd() {
 	${ABUILD_LOG_CMD:-true} "$@"