kiss-manifest: clean up

contrib/kiss-manifest

@@ -1,16 +1,11 @@
 #!/bin/sh -ef
 # Display all files owned by a package
 
-# Use the current directory as the package name if no package is given.
-[ "$1" ] || {
-    set -- "${PWD##*/}"
-}
+pkg=${1:-"${PWD##*/}"}
 
-# Ignore shellcheck as we want the warning's behavior.
-# shellcheck disable=2015
-kiss list "${1:-null}" >/dev/null || {
-    printf 'usage: kiss-manifest [pkg]\n'
+kiss list "$pkg" >/dev/null || {
+    printf 'usage: kiss-manifest [pkg]\n' >&2
     exit 1
 }
 
-cat "$KISS_ROOT/var/db/kiss/installed/$1/manifest" 2>/dev/null
+cat "$KISS_ROOT/var/db/kiss/installed/$pkg/manifest" 2>/dev/null