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 <jason77.wang@gmail.com>
and Tony Lindgren <tony@atomide.com>, and fix for versatile express from
Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>.

Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Jason Wang <jason77.wang@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Tested-by: Kevin Hilman <khilman@deeprootsystems.com>
arm: use addruart macro to establish debug mappings

Since we can get both physical and virtual addresses from the addruart
macro, we can use this to establish the debug mappings.

In the case of CONFIG_DEBUG_ICEDCC, we don't need any mappings, but
may still need to setup r7 correctly.

Incorporating ASM changes from Nicolas Pitre <npitre@fluxnic.net>.

Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Tested-by: Kevin Hilman <khilman@deeprootsystems.com>
Merge commit 'c293393faa8e11a5a80a9e358718432b8697f451' into partial2