x86, UV: Delete mapping of MMR rangs mapped by BIOS

The UV BIOS has added additional MMR ranges that are mapped via
EFI virtual mode mappings. These ranges should be deleted from
ranges mapped by uv_system_init().

Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: linux-mm@kvack.org
LKML-Reference: <20090727143656.GA7698@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>