staging/mei: MEI driver init flow.

Init driver list and queue, MEI Hardware reset flow,
init of driver specific host client.

MEI Init/reset flow:
- Ack all waiting interrupts
- Hardware reset flow (Set Reset Bit, Generate Interrupt, Clear Reset Bit
  Generate Interrupt)
- Wait for ME Ready Bit (done in interrupt thread)
- Set ME Ready Bit (done in interrupt thread)
- Send Start request (done in interrupt thread)
- wait for answer
- Send Enumerate Clients request (done in interrupt thread)
- wait for answer
- Send Get Client property for each client request (done in interrupt thread)
- Wait for answers
- Init Done.

MEI Driver connect internally to 2 ME clients/features:
AMTHI and AMT watchdog.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Itzhak Tzeel-Krupp <itzhak.tzeel-krupp@intel.com>
Signed-off-by: Oren Weil <oren.jer.weil@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>