The return value of memblock_x86_check_reserved_size() doesn't
indicate whether there's an overlapping reservatoin or not.  It
indicates whether the caller needs to iterate further to discover all
reserved portions of the specified area.

efi_reserve_boot_esrvices() wants to check whether the boot services
area overlaps with other reservations but incorrectly used
membloc_x86_check_reserved_size().  Use memblock_is_region_reserved()
instead.
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310457490-3356-2-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>