Fix the key value generation for get/set amp verbs.  The upper bits of
the parameter have to be combined with the verb value to be unique for
each direction/index of amp access.

This fixes the resume problem on some hardwares like Macbook after
the channel mode is changed.
Tested-by: NJohannes Berg <johannes@sipsolutions.net>
Cc: <stable@kernel.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>