PPC: Disable wasm simd load store testcase

For this testcase to run on BE, it requires Load/store
reversed byte instructions. Disabling testcase until
the necessary instructions are implemented.

R=machenbach@chromium.org, jkummerow@chromium.org
BUG=
LOG=N

Change-Id: I380c9a07030ba12e9b9e81c372496819102e2b0d
Reviewed-on: https://chromium-review.googlesource.com/595047Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Jaideep Bajwa <bjaideep@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#47023}

test/cctest/cctest.status

@@ -316,6 +316,8 @@
   'test-run-wasm-module/Run_WasmModule_Return114' : [SKIP],
   'test-run-wasm-module/Run_WasmModule_CallAdd' : [SKIP],
   'test-run-wasm-module/Run_WasmModule_CallMain_recursive' : [SKIP],
+  # TODO(ppc): Implement load/store reverse byte instructions
+  'test-run-wasm-simd/RunWasmCompiled_SimdLoadStoreLoad': [SKIP],
 
 }],  # 'system == aix or (arch == ppc64 and byteorder == big)'