vgchange autoactivation: skip regex filter containing symlinks

"vgchange -aay --autoactivation event" is called by our udev rule.
When the udev rule runs, symlinks for devices may not all be created
yet.  If the regex filter contains symlinks, it won't work correctly.
This command uses devices that already passed through pvscan.  Since
pvscan applies the regex filter correctly, this command inherits the
filtering from pvscan and can skip the regex filter itself.

See the previous commit
"pvscan: use alternate device names from DEVLINKS to check filter"

lib/commands/toolcontext.h

@@ -194,6 +194,7 @@ struct cmd_context {
 	unsigned create_edit_devices_file:1;	/* command expects to create and/or edit devices file */
 	unsigned edit_devices_file:1;		/* command expects to edit devices file */
 	unsigned filter_deviceid_skip:1;	/* don't use filter-deviceid */
+	unsigned filter_regex_skip:1;		/* don't use filter-regex */
 	unsigned filter_regex_with_devices_file:1; /* use filter-regex even when devices file is enabled */
 	unsigned filter_nodata_only:1;          /* only use filters that do not require data from the dev */
 	unsigned run_by_dmeventd:1;		/* command is being run by dmeventd */