Merge tag 'tty-4.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Merge tag 'tty-4.15-rc3' of git://git./linux/kernel/git/gregkh/tty

Pull tty/serial driver fixes from Greg KH:
 "Here are some small serdev and serial fixes for 4.15-rc3. They resolve
  some reported problems:

   - a number of serdev fixes to resolve crashes

   - MIPS build fixes for their serial port

   - a new 8250 device id

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-4.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  MIPS: Add custom serial.h with BASE_BAUD override for generic kernel
  serdev: ttyport: fix tty locking in close
  serdev: ttyport: fix NULL-deref on hangup
  serdev: fix receive_buf return value when no callback
  serdev: ttyport: add missing receive_buf sanity checks
  serial: 8250_early: Only set divisor if valid clk & baud
  serial: 8250_pci: Add Amazon PCI serial device ID