Bluetooth: hci_qca: Give enough time to ROME controller to bootup.

This patch enables enough time to ROME controller to bootup
after we bring the enable pin out of reset.

Fixes: 05ba533c ("Bluetooth: hci_qca: Add serdev support").
Signed-off-by: Balakrishna Godavarthi <bgodavar@codeaurora.org>
Reviewed-by: Rocky Liao <rjliao@codeaurora.org>
Tested-by: Rocky Liao <rjliao@codeaurora.org>
Tested-by: Claire Chang <tientzu@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>