mei: bus: unconditionally enable clients with vtag support

mei: bus: unconditionally enable clients with vtag support

The list of clients is only visible via mei client bus.
Enabling vtag clients on the mei client bus allows user-space to
enumerate clients with vtag support by traversing the mei bus on sysfs.
This feature is required for ACRN device model service.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20200818115147.2567012-11-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>