staging/mei: Interrupt handling.

ISR and interrupt thread for handling incoming data.
e.g. read bus message, read client message, handle reset requests.

quick handler:
	As MEI may share interrupt with GFX and/or USB
	the HW register need to be checked and acknowledged.

thread handler:
	Check if HW has data for read.
	Write data to HW if possible.
	May init reset flow on error

there can be two types of messages:
1) bus messages:
	Management messages between MEI Driver and ME e.g.
		Connect request/response,
		Disconnect request/response
		Enum clients request/response
		Flow control request/response
	those message are indicated by
	ME Address/ID == 0 && Host Address/ID == 0

2) feature/client messages:
	message that are sends between ME Feature/Client and
	an application, the struct of the message is defined
	by the ME Feature Protocol (e.g. APF Protocol, AMTHI Protocol)
	those message are indicated by
	ME Address/ID != 0 && Host Address/ID != 0

MEI Initialization state machine is also managed by this patch.
After MEI Reset is preform:
	Send Start request
		wait for answer
	Send Enumerate Clients request
		wait for answer
	Send Get Client property for each client request
		wait for answers
	Init Done.

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>