imx: Use generic console_t data structure

Since now the generic console_t structure holds the UART base address as
well, let's use that generic location and drop the UART driver specific
data structure at all.

Change-Id: I058f793e4024fa7291e432f5be374a77faf16f36
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
8 files changed