x86: fix trimming e820 with MTRR holes. - fix

v2: process hole then end_pfn
    fix update_memory_range with whole cover comparing

Signed-off-by: Yinghai Lu <yinghai.lu@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>