Extend imx6q DEBUG_LL uart port selection support to cover all i.MX
SoCs.  The 'range' of the Kconfig option gets dropped, as users
looking at the option must know the uart number on his board.  The
bottom line is that the build system will report an error if an
invalid port number is picked for given SoC.

The header arch/arm/include/debug/imx-uart.h is created to accommodate
all the uart base addresses.  And the header will also be used for
other low-level debug facility later.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

Only mx508 based board is mach-mx50_rdp and it has been marked as BROKEN
for several releases.

mx508 currently lacks clock support.

In case someone needs to add mx508 support back, then the recommended approach
is to use device tree.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

imx6q gets 5 uart ports in total.  Different board design may choose
different port as debug uart.  For example, imx6q-sabresd uses UART1,
imx6q-sabrelite uses UART2 and imx6q-arm2 uses UART4.  Rather than
bloating DEBUG_LL choice list with all these uart ports, the patch
introduces DEBUG_IMX6Q_UART_PORT for users to input uart port number
when DEBUG_IMX6Q_UART is selected inside DEBUG_LL choice.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

Move imx debug-macro.S over to common debug macro directory.  It
removes the inclusion to hardware.h by hard-coding the physical
address of uart port and copying IMX_IO_P2V from hardware.h.

Since we will need a common solution, which might use a fixed virtual
address for uart port across platforms, we make a copy of IMX_IO_P2V
here as a temporary solution to enable low-level debug for imx
multi-platform build.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>