powerpc/85xx: don't display address map size (32-bit vs. 36-bit) during boot

Most 85xx boards can be built as a 32-bit or a 36-bit.  Current code sometimes
displays which of these is actually built, but it's inconsistent.  This is
especially problematic since the "default" build for a given 85xx board can
be either one, so if you don't see a message, you can't always know which
size is being used.  Not only that, but each board includes code that displays
the message, so there is duplication.

The 'bdinfo' command has been updated to display this information, so
we don't need to display it at boot time.  The board-specific code is
deleted.

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>