mwifiex: fix hung task on command timeout

Sometimes when command timeout occurs due to a firmware or
hardware bug, there may be some synchronous commands in command
queue. These commands are never downloaded to firmware causing
hung task warnings. This patch replaces wait_event_interruptible
call with wait_event_interruptible_timeout to fix the issue.

Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Avinash Patil <patila@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>