[PATCH] hpet: use HPET physical addresses for dup. detection

- Use HPET physical address to detect duplicates, not logical addresses.
  Using logical (mapped) addresses fails to detect duplicates
  because ioremap() returns a new mapped address each time.

- iounmap() regions when duplicate/busy areas are found.

Signed-off-by: Randy Dunlap <randy_d_dunlap@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>