Structure for String.Equals intrinsic

Added structure for implementing String.Equals intrinsics. There is no
functional change at this point- the intrinsic is marked as unimplemented
for all instruction sets and compilers.

Bug: 21481923
Change-Id: Ic2a1e22a113ff6091581126f12e926478c011340
diff --git a/compiler/optimizing/intrinsics.cc b/compiler/optimizing/intrinsics.cc
index a3cb144..c5ba8cb 100644
--- a/compiler/optimizing/intrinsics.cc
+++ b/compiler/optimizing/intrinsics.cc
@@ -211,6 +211,8 @@
       return Intrinsics::kStringCharAt;
     case kIntrinsicCompareTo:
       return Intrinsics::kStringCompareTo;
+    case kIntrinsicEquals:
+      return Intrinsics::kStringEquals;
     case kIntrinsicGetCharsNoCheck:
       return Intrinsics::kStringGetCharsNoCheck;
     case kIntrinsicIsEmptyOrLength: