x86: Fix error return sequence in __ioremap_caller()

x86: Fix error return sequence in __ioremap_caller()

kernel missed to free memtype if get_vm_area_caller failed in
__ioremap_caller.

This patch introduces error path to fix this and cleans up the
repetitive error return sequences that contributed to the
creation of the bug.

Signed-off-by: Xiaotian Feng <[email protected]>
Acked-by: Suresh Siddha <[email protected]>
Cc: Venkatesh Pallipadi <[email protected]>
Cc: H. Peter Anvin <[email protected]>
LKML-Reference: <1257389031[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>