serial: qcom-geni: drop bogus uart_write_wakeup()

Drop the bogus uart_write_wakeup() from when setting up a new DMA
transfer, which does not free up any more space in the ring buffer.

Any pending writers will be woken up when the transfer completes.

Cc: stable <stable@kernel.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Tested-by: Andrew Halaney <ahalaney@redhat.com> # sa8540p-ride
Link: https://lore.kernel.org/r/20230307164405.14218-5-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/qcom_geni_serial.c

@@ -634,10 +634,6 @@ static void qcom_geni_serial_start_tx_dma(struct uart_port *uport)
 	if (uart_circ_empty(xmit))
 		return;
 
-	xmit_size = uart_circ_chars_pending(xmit);
-	if (xmit_size < WAKEUP_CHARS)
-		uart_write_wakeup(uport);
-
 	xmit_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
 
 	qcom_geni_serial_setup_tx(uport, xmit_size);