serial: imx: Support DTE mode ...

Based on Kernel commit 20ff2fe60a: serial: imx: add support for DTE mode

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Merge branch 'for-next/vincell'

ARM: i.MX: make early UART functions independent of DEBUG_LL ...

We have functions to setup the i.MX uart for early use, but these all
depend on DEBUG_LL. Move them to imx-uart.h to make them usable for
the regular PBL console.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

i.MX: serial: Add baud rate calculation convenience functions ...

Add two functions to calculate values for UBMR and UBIR
registers. This way both early serial initalization code and
serial_imx.c can use them and not duplicate the code.

Singed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

i.MX: serial: Add constants for UART clock divisor ...

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

i.MX: Move UART definitions into a separate file ...

Move UART definitions into a separate file to avoid redefinition in
<mach/debug_ll.h> and magical constants in low level UART
initialization code.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>