Stop stomping 'mname' global

Define it as local and keep it.

src/shellfu.sh.skel

@@ -185,6 +185,7 @@ shellfu() {
             # Show version of module named $1
             #
             local mname=$1
+            local mpath
             mpath=$(shellfu _select_mfile "$mname") || {
                 shellfu __warn "cannot find module: $mname"
                 return 3