tty: serial: men_z135_uart: Wakeup UART after transmitting
tty: serial: men_z135_uart: Wakeup UART after transmitting

Call uart_write_wakeup() after writing the hardware FIFO and updateing the FIFO
pointers.

This fixes high latency and jitter on PPP over Serial links.

Reported-by: Jun Shih <3f543b5029b9f58957722d186dd0dce150154250@pason.com>
Tested-by: Jun Shih <3f543b5029b9f58957722d186dd0dce150154250@pason.com>
Signed-off-by: Johannes Thumshirn <b9c174c636bbd21512daa87cec4e52ffa14f4a5a@men.de>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@linuxfoundation.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs