Bluetooth: btmrvl: avoid sending data to firmware after hs_activated

We should suspend hci device and purge remaining data in tx queue
before enabling host sleep in firmware. If any data is sent to
firmware after host sleep is activated, firmware may end up
sending a TX_DONE interrupt to driver. If this interrupt gets
delivered to host while the SDIO host controller is suspending,
it may crash the system.

Conversely, in resume handler, we should resume hci device after
host sleep is de-activated.

Signed-off-by: Chin-Ran Lo <crlo@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>