Rename WebAssembly SIMD source files and functions with x86 or arm suffix after wasmsimd

- BUILD/CMakeLists.txt sorted alpha numberically

PiperOrigin-RevId: 346133603
diff --git a/src/f32-igemm/wasmsimd-splat.c.in b/src/f32-igemm/wasmsimd-splat.c.in
index 244eebf..8d3d6a1 100644
--- a/src/f32-igemm/wasmsimd-splat.c.in
+++ b/src/f32-igemm/wasmsimd-splat.c.in
@@ -16,7 +16,7 @@
 $ACTIVATION_SUFFIX = {"LINEAR": ""}.get(ACTIVATION, "_" + ACTIVATION.lower())
 $ARCH_SUFFIX = "" if ACTIVATION in ["LINEAR", "RELU"] else "_x86" if X86 else "_arm"
 $PARAMS = {"LINEAR": "xnn_f32_default_params", "RELU": "xnn_f32_relu_params", "MINMAX": "xnn_f32_minmax_params"}[ACTIVATION]
-void xnn_f32_igemm${ACTIVATION_SUFFIX}_ukernel_${MR}x${NR}__wasmsimd_splat${ARCH_SUFFIX}(
+void xnn_f32_igemm${ACTIVATION_SUFFIX}_ukernel_${MR}x${NR}__wasmsimd${ARCH_SUFFIX}_splat(
     size_t mr,
     size_t nc,
     size_t kc,