Bluetooth: btmrvl: max out host sleep parameter 'gap'

For gpio=0xff (wake up host through SDIO interface) case,
gap=0xff means no delay (same as gap=0) for incoming data packet
to be sent to host after host sleep is activated.
Change it to the maximum delay to reduce the chance that RX
interrupt could be delivered while host controller suspends.

Signed-off-by: Chin-Ran Lo <crlo@marvell.com>
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>