Move OS::MemCopy and OS::MemMove out of platform to utils

src/hydrogen-check-elimination.cc

Index: src/hydrogen-check-elimination.cc
diff --git a/src/hydrogen-check-elimination.cc b/src/hydrogen-check-elimination.cc
index f3c5cbe151e3e7e1615834bf3834927158e03f78..506a04588995fbd25c858424b1461adf1155b781 100644
--- a/src/hydrogen-check-elimination.cc
+++ b/src/hydrogen-check-elimination.cc
@@ -622,9 +622,9 @@ class HCheckTable : public ZoneObject {
       int L = cursor_;
       int R = size_ - cursor_;
 
-      OS::MemMove(&tmp_entries[0], &entries_[0], L * sizeof(HCheckTableEntry));
-      OS::MemMove(&entries_[0], &entries_[L], R * sizeof(HCheckTableEntry));
-      OS::MemMove(&entries_[R], &tmp_entries[0], L * sizeof(HCheckTableEntry));
+      MemMove(&tmp_entries[0], &entries_[0], L * sizeof(HCheckTableEntry));
+      MemMove(&entries_[0], &entries_[L], R * sizeof(HCheckTableEntry));
+      MemMove(&entries_[R], &tmp_entries[0], L * sizeof(HCheckTableEntry));
     }
 
     cursor_ = size_;  // Move cursor to end.