Remove over aggresive assert tripping up image_test

Change-Id: I3fe34c069b70536665fc97ef34b266e986eeca4e
diff --git a/src/image_writer.cc b/src/image_writer.cc
index 611dce1..d0e3579 100644
--- a/src/image_writer.cc
+++ b/src/image_writer.cc
@@ -468,7 +468,6 @@
 
     uint32_t gc_map_offset = orig->GetOatGcMapOffset();
     const byte* gc_map = GetOatAddress(gc_map_offset);
-    CHECK(gc_map != NULL || orig->IsRuntimeMethod()) << PrettyMethod(orig);
     copy->gc_map_ = reinterpret_cast<const uint8_t*>(gc_map);
   }
 }