mm: Use correct define for CMA features

CMA features may ifdef out parts of the code with
CONFIG_CMA. Older code uses CONFIG_DMA_CMA. Switch
to using the newer CONFIG_CMA to ensure the code gets
compiled when needed.

Change-Id: I3cae639797787b4926a6c5e057de973b66196707
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Neha Pandey <nehap@codeaurora.org>
diff --git a/mm/memory.c b/mm/memory.c
index b2baf36..a240b04 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2900,7 +2900,7 @@
 	entry = pte_to_swp_entry(orig_pte);
 	if (unlikely(non_swap_entry(entry))) {
 		if (is_migration_entry(entry)) {
-#ifdef CONFIG_DMA_CMA
+#ifdef CONFIG_CMA
 			/*
 			 * FIXME: mszyprow: cruel, brute-force method for
 			 * letting cma/migration to finish it's job without