iwmbtfw(8): Improve 7260 adaptors handling

[wulf]

Summary

• Allow firmware downloading for hw_variant #8
• Enter manufacturer mode for setting of event mask
• Handle multi-event response on HCI commands for 7260 This allows to remove kludge with skipping of 0xfc2f opcode
• Disable patch and exit manufacturer mode on downloading failure
• Use default firmware if correct firmware file is not found.

Test Plan

test on intel 7260/7265 bluetooth adaptor

[pitwuu_gmail.com]

		/*
		 * Every command has its associated event: data must match
		 * what is recorded in the firmware file. Perform that check
		 * now.
		 *
		 * Some commands are mapped to more than one event sequence,
		 * in that case we can drop the non-patch commands, as we
		 * probably don't need them for operation of the card.
		 *
		 */

This comment could possibly be modified to remove the part about dropping commands.

[pitwuu_gmail.com]

Tested. It works and is good to go. Intel 7260.
One nit: we have files from iwmbt-firmware located @ /usr/local/share/iwmbt-firmware/
and this present utility looks in /usr/share/firmware/intel.
Maybe we could make it look sequentially in one, then the other. ?