Update image oat checksum when patching

Change-Id: I766d2745bc817a5cb3a36d62bc733bab43a31fe0
diff --git a/src/class_linker.cc b/src/class_linker.cc
index 007b8a6..b96db3e 100644
--- a/src/class_linker.cc
+++ b/src/class_linker.cc
@@ -707,7 +707,7 @@
   uint32_t image_oat_checksum = image_header.GetOatChecksum();
   if (oat_checksum != image_oat_checksum) {
     LOG(ERROR) << "Failed to match oat file checksum " << std::hex << oat_checksum
-               << " to expected oat checksum " << std::hex << oat_checksum
+               << " to expected oat checksum " << std::hex << image_oat_checksum
                << " in image";
     return NULL;
   }