Enable Wasm spec tests for SIMD load_splat (bytecodealliance#1426)

Author: abrown

build.rs

@@ -189,7 +189,6 @@ fn ignore(testsuite: &str, testname: &str, strategy: &str) -> bool {
             ("simd", "simd_lane") => return true, // FIXME invalid u8 number: constant out of range: (v8x16.shuffle -1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14...
             ("simd", "simd_load") => return true, // FIXME Unsupported feature: proposed SIMD operator I8x16Shl
             ("simd", "simd_load_extend") => return true, // FIXME Unsupported feature: proposed SIMD operator I16x8Load8x8S { memarg: MemoryImmediate { flags: 0, offset: 0 } }
-            ("simd", "simd_load_splat") => return true, // FIXME Unsupported feature: proposed SIMD operator V8x16LoadSplat { memarg: MemoryImmediate { flags: 0, offset: 0 } }
             ("simd", "simd_splat") => return true, // FIXME Unsupported feature: proposed SIMD operator I8x16ShrS
 
             // Still working on implementing these. See #929.