macOS don't need to disable avx2 explictly

Author: crazywhalecc

src/SPC/builder/unix/library/libwebp.php

@@ -13,7 +13,7 @@ protected function build(): void
         $code = 'int main() { return _mm256_cvtsi256_si32(_mm256_setzero_si256()); }';
         $cc = getenv('CC') ?: 'gcc';
         [$ret] = shell()->execWithResult("echo '{$code}' | {$cc} -x c -mavx2 -o /dev/null - 2>&1");
-        $disableAvx2 = $ret !== 0 && GNU_ARCH === 'x86_64';
+        $disableAvx2 = $ret !== 0 && GNU_ARCH === 'x86_64' && PHP_OS_FAMILY === 'Linux';
 
         UnixCMakeExecutor::create($this)
             ->addConfigureArgs(