[WASM] Fix failing Wasm SIMD F32x4 tests.

- Perform lane checks using FP compare instead of reinterpret casts. 0 and -0
will be different under I32 compare.
- Some arithmetic operations can generate NaN results, such as adding -Inf
and +Inf. Skip these tests until we have a way to do more sophisticated
FP comparisons in the SIMD tests.
- Eliminate a redundant F32x4 parameter for FP SIMD vector checking. We will only have this one FP type.

LOG=N
BUG=v8:6020

Review-Url: https://codereview.chromium.org/2594043002
Cr-Original-Commit-Position: refs/heads/master@{#42154}
Committed: https://chromium.googlesource.com/v8/v8/+/5560bbb498252334595a39bb5f313ac8eb82cfe1
Review-Url: https://codereview.chromium.org/2594043002
Cr-Commit-Position: refs/heads/master@{#43528}

test/cctest/cctest.status

@@ -244,10 +244,6 @@
   'test-serialize/StartupSerializerTwice': [SKIP],
   'test-serialize/StartupSerializerOnceRunScript': [SKIP],
   'test-serialize/StartupSerializerTwiceRunScript': [SKIP],
-  'test-run-wasm-simd/RunWasmCompiled_F32x4Add': [SKIP],
-  'test-run-wasm-simd/RunWasmCompiled_F32x4Sub': [SKIP],
-  'test-run-wasm-simd/RunWasmInterpreted_F32x4Add': [SKIP],
-  'test-run-wasm-simd/RunWasmInterpreted_F32x4Sub': [SKIP],
 
   ############################################################################
   # Slow tests.