mm: remove obsolete macro NR_PCP_ORDER_MASK and NR_PCP_ORDER_WIDTH

Since commit 8b10b465 ("mm/page_alloc: free pages in a single pass
during bulk free"), they're not used anymore.  Remove them.

Link: https://lkml.kernel.org/r/20220916072257.9639-4-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/mmzone.h

@@ -564,13 +564,6 @@ enum zone_watermarks {
 #define NR_LOWORDER_PCP_LISTS (MIGRATE_PCPTYPES * (PAGE_ALLOC_COSTLY_ORDER + 1))
 #define NR_PCP_LISTS (NR_LOWORDER_PCP_LISTS + NR_PCP_THP)
 
-/*
- * Shift to encode migratetype and order in the same integer, with order
- * in the least significant bits.
- */
-#define NR_PCP_ORDER_WIDTH 8
-#define NR_PCP_ORDER_MASK ((1<<NR_PCP_ORDER_WIDTH) - 1)
-
 #define min_wmark_pages(z) (z->_watermark[WMARK_MIN] + z->watermark_boost)
 #define low_wmark_pages(z) (z->_watermark[WMARK_LOW] + z->watermark_boost)
 #define high_wmark_pages(z) (z->_watermark[WMARK_HIGH] + z->watermark_boost)

mm/page_alloc.c

@@ -1584,7 +1584,6 @@ static void free_pcppages_bulk(struct zone *zone, int count,
 
 		order = pindex_to_order(pindex);
 		nr_pages = 1 << order;
-		BUILD_BUG_ON(MAX_ORDER >= (1<<NR_PCP_ORDER_WIDTH));
 		do {
 			int mt;