PPC: disable SimdLoadStoreLoad

Disable test on big endian PPC for now, since it
is missing load/store reverse byte instructions.

R=machenbach@chromium.org, jkummerow@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com
BUG=
LOG=N

Change-Id: Iaf12a14678bc9d113dc4d11998ea5bad158c20fd
Reviewed-on: https://chromium-review.googlesource.com/634271Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Jaideep Bajwa <bjaideep@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#47587}

test/cctest/cctest.status

@@ -318,6 +318,7 @@
   'test-run-wasm-module/Run_WasmModule_CallMain_recursive' : [SKIP],
   # TODO(ppc): Implement load/store reverse byte instructions
   'test-run-wasm-simd/RunWasmCompiled_SimdLoadStoreLoad': [SKIP],
+  'test-run-wasm-simd/RunWasm_SimdLoadStoreLoad': [SKIP],
 
 }],  # 'system == aix or (arch == ppc64 and byteorder == big)'