bootmem: Add alloc_bootmem_align()

Add an alloc_bootmem_align() interface to allocate bootmem with
specified alignment.  This is necessary to be able to allocate the
xsave area in a subsequent patch.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20101116212441.977574826@sbsiddha-MOBL3.sc.intel.com>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@kernel.org>

include/linux/bootmem.h

@@ -105,6 +105,8 @@ extern void *__alloc_bootmem_low_node(pg_data_t *pgdat,
 
 #define alloc_bootmem(x) \
 	__alloc_bootmem(x, SMP_CACHE_BYTES, __pa(MAX_DMA_ADDRESS))
+#define alloc_bootmem_align(x, align) \
+	__alloc_bootmem(x, align, __pa(MAX_DMA_ADDRESS))
 #define alloc_bootmem_nopanic(x) \
 	__alloc_bootmem_nopanic(x, SMP_CACHE_BYTES, __pa(MAX_DMA_ADDRESS))
 #define alloc_bootmem_pages(x) \