Fix oatdump "compilercallbacks" option for runtime.

The "compilercallbacks" runtime option replaced "compiler"
in I708ca13227c809e07917ff3879a89722017e83a9 .

Fix a comment in codegen_util.cc .

Change-Id: I2c5ebd56dd96f0ee8e62b602bfe45357565471ff
diff --git a/compiler/dex/quick/codegen_util.cc b/compiler/dex/quick/codegen_util.cc
index 65286d5..29554c0 100644
--- a/compiler/dex/quick/codegen_util.cc
+++ b/compiler/dex/quick/codegen_util.cc
@@ -1003,7 +1003,7 @@
 
   /*
    * Custom codegen for special cases.  If for any reason the
-   * special codegen doesn't succeed, first_lir_insn_ will
+   * special codegen doesn't succeed, first_lir_insn_ will be
    * set to NULL;
    */
   // TODO: Clean up GenSpecial() and return true only if special implementation is emitted.