tune2fs: Add missing return in -M arg completion

bash_completion

@@ -1963,7 +1963,7 @@ _completion_loader()
     local cmd="${1:-_EmptycmD_}" compdir=./completions compfile
     [[ $BASH_SOURCE == */* ]] && compdir="${BASH_SOURCE%/*}/completions"
 
-    for compfile in "${cmd##*/}" _"${cmd##*/}"; do
+    for compfile in "${cmd##*/}" "${cmd##*/}".bash _"${cmd##*/}"; do
         compfile="$compdir/$compfile"
         # Avoid trying to source dirs; https://bugzilla.redhat.com/903540
         [[ -f "$compfile" ]] && . "$compfile" &>/dev/null && return 124

completions/tune2fs

@@ -20,6 +20,7 @@ _tune2fs()
             ;;
         -M)
             _filedir -d
+            return 0
             ;;
         -o)
             local -a opts=(^debug ^bsdgroups ^user_xattr ^acl ^uid16