Document the pg_upgrade -j/--jobs option as taking an argument

doc/src/sgml/ref/pgupgrade.sgml

@@ -114,8 +114,8 @@
      </varlistentry>
 
      <varlistentry>
-      <term><option>-j</option></term>
-      <term><option>--jobs</option></term>
+      <term><option>-j <replaceable class="parameter">njobs</replaceable></option></term>
+      <term><option>--jobs=<replaceable class="parameter">njobs</replaceable></option></term>
       <listitem><para>number of simultaneous processes or threads to use
       </para></listitem>
      </varlistentry>

src/bin/pg_upgrade/option.c

@@ -295,7 +295,7 @@ usage(void)
 	printf(_("  -c, --check                   check clusters only, don't change any data\n"));
 	printf(_("  -d, --old-datadir=DATADIR     old cluster data directory\n"));
 	printf(_("  -D, --new-datadir=DATADIR     new cluster data directory\n"));
-	printf(_("  -j, --jobs                    number of simultaneous processes or threads to use\n"));
+	printf(_("  -j, --jobs=NUM                number of simultaneous processes or threads to use\n"));
 	printf(_("  -k, --link                    link instead of copying files to new cluster\n"));
 	printf(_("  -o, --old-options=OPTIONS     old cluster options to pass to the server\n"));
 	printf(_("  -O, --new-options=OPTIONS     new cluster options to pass to the server\n"));