[PATCH v4 0/2] ns16550-related patches

[Antony Pavlov]

This patch series consist of two ns16550-related patches.

[PATCH v4 1/4] ns16550: support for UART with broken FIFO
[PATCH v4 2/4] ns16550: make ns16550_serial_init_port() shorter
[PATCH v4 3/4] ns16550: write zero to ier only once
[PATCH v4 4/4] ns16550: fix ier selection

The 1st one adds the flag (NS16650_FLAG_DISABLE_FIFO) in internal
ns16550 data structure to recognise UART with broken FIFO
(or UART without FIFO at all) and the code to use this flag.
The flag can be set in board-related code.

The 2nd one use the fact that ns16550_serial_init_port() and
ns16550_setbaudrate() functions have many common code.
It change the most of ns16550_serial_init_port() code for
one ns16550_setbaudrate() call.

The 3rd one removes unnecessary interrupt disable on every
speed change operation.

The 4th one adds explicit IER register selection before accessing it.