mm/hpa: add alloc_pages_highorder_except()

mm/hpa: add alloc_pages_highorder_except()

alloc_pages_highorder() allocates given number of pages of given order.
It is a page allocator with a restriction of page order. Therefore, it
is used by the drivers of H/Ws with a requirement of higher memory
alignment than PAGE_SIZE.
Moreover some H/W have additional restriction of memory addressing.
They are not accessible to some range of memory.
alloc_pages_highorder_except() provides a way to avoid unaccessible
memory area to HPA not to allocate inappropriate pages to the drivers.

Change-Id: I6c5fe40c7dd5367ea15eb69c7bf68325070dafa4
Signed-off-by: Cho KyongHo <pullip.cho@samsung.com>