serial: qcom-geni: Add support for 8 Mbps baud rate

Current GENI UART driver supports Max Baud rate up to 4 Mbps.
Add support to increase maximum baud rate to 8 Mbps.

Signed-off-by: Jyothi Kumar Seerapu <[e-mail]>
Reviewed-by: Dmitry Baryshkov <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/tty/serial/qcom_geni_serial.c

···
 	unsigned long timeout;
 
 	/* baud rate */
-	baud = uart_get_baud_rate(uport, termios, old, 300, 4000000);
+	baud = uart_get_baud_rate(uport, termios, old, 300, 8000000);
 
 	sampling_rate = UART_OVERSAMPLING;
 	/* Sampling rate is halved for IP versions >= 2.5 */