arm: return both physical and virtual addresses from addruart

arm: return both physical and virtual addresses from addruart

Rather than checking the MMU status in every instance of addruart, do it
once in kernel/debug.S, and change the existing addruart macros to
return both physical and virtual addresses. The main debug code can then
select the appropriate address to use.

This will also allow us to retreive the address of a uart for the MMU
state that we're not current in.

Updated with fixes for OMAP from Jason Wang <[email protected]>
and Tony Lindgren <[email protected]>, and fix for versatile express from
Lorenzo Pieralisi <[email protected]>.

Signed-off-by: Jeremy Kerr <[email protected]>
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Jason Wang <[email protected]>
Signed-off-by: Tony Lindgren <[email protected]>
Tested-by: Kevin Hilman <[email protected]>