tty: serial: qcom_geni_serial: Fix RX cancel command failure

commit 679aac5e upstream.

RX cancel command fails when BT is switched on and off multiple times.

To handle this, poll for the cancel bit in SE_GENI_S_IRQ_STATUS register
instead of SE_GENI_S_CMD_CTRL_REG.

As per the HPG update, handle the RX last bit after cancel command
and flush out the RX FIFO buffer.

Signed-off-by: satya priya <skakit@codeaurora.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1581415982-8793-1-git-send-email-skakit@codeaurora.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>