[coreboot] Untangling the UART

[Kyösti Mälkki]

Hey!

I have posted first half for series of patches that should untangle
the mess of multiple different prototypes for the simple thing of 
getting some console output out of UART.

There is little practical use of being able to compile coreboot with 
multiple type of UARTs in same build, so we can use same function 
prototypes for all different type of UARTs once we sort out the issue 
with passing the base address argument. Solving this part is available 
for review now on gerrit.

Easiest way to access these in gerrit is to find CL
'SMM: Only have console with DEBUG_SMI', and check its dependencies.

http://review.coreboot.org/#/c/5142

Thanks,
   Kyösti