mm: rename gfpflags_to_migratetype to gfp_migratetype for same convention

Pageblock migrate type is encoded in GFP flags, just as zone_type and
zonelist.

Currently we use gfp_zone() and gfp_zonelist() to extract related
information, it would be proper to use the same naming convention for
migrate type.

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Link: http://lkml.kernel.org/r/20200329080823.7735-1-richard.weiyang@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 818c264..2bd8d68 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4285,7 +4285,7 @@ gfp_to_alloc_flags(gfp_t gfp_mask)
 		alloc_flags |= ALLOC_HARDER;
 
 #ifdef CONFIG_CMA
-	if (gfpflags_to_migratetype(gfp_mask) == MIGRATE_MOVABLE)
+	if (gfp_migratetype(gfp_mask) == MIGRATE_MOVABLE)
 		alloc_flags |= ALLOC_CMA;
 #endif
 	return alloc_flags;
@@ -4735,7 +4735,7 @@ static inline bool prepare_alloc_pages(gfp_t gfp_mask, unsigned int order,
 	ac->highest_zoneidx = gfp_zone(gfp_mask);
 	ac->zonelist = node_zonelist(preferred_nid, gfp_mask);
 	ac->nodemask = nodemask;
-	ac->migratetype = gfpflags_to_migratetype(gfp_mask);
+	ac->migratetype = gfp_migratetype(gfp_mask);
 
 	if (cpusets_enabled()) {
 		*alloc_mask |= __GFP_HARDWALL;