Fix the signature of the IndexOf entry point.

The IndexOf entry point was declared as taking four
arguments (void*, uint32_t, uint32_t, uint32_t) whereas all
actual implementations use three arguments (void*, uint32_t,
uint32_t).  As that fourth argument is not documented, drop
it from the intrinsic declaration to have it match the
implementations.

Change-Id: I65d747033192025ccd2b9a5e8f8ed05b77a21941
diff --git a/compiler/optimizing/intrinsics_arm64.cc b/compiler/optimizing/intrinsics_arm64.cc
index 4be1695..ce595c5 100644
--- a/compiler/optimizing/intrinsics_arm64.cc
+++ b/compiler/optimizing/intrinsics_arm64.cc
@@ -1301,6 +1301,7 @@
   }
 
   __ Ldr(lr, MemOperand(tr, QUICK_ENTRYPOINT_OFFSET(kArm64WordSize, pIndexOf).Int32Value()));
+  CheckEntrypointTypes<kQuickIndexOf, int32_t, void*, uint32_t, uint32_t>();
   __ Blr(lr);
 
   if (slow_path != nullptr) {