hack to fix compilation on avx2 intel macbook

Author: LostRuins

ggml/src/ggml-cpu/arch/x86/repack.cpp

@@ -737,7 +737,7 @@ void ggml_gemv_q4_K_8x8_q8_K(int n, float * GGML_RESTRICT s, size_t bs, const vo
     UNUSED(ncols_interleaved);
     UNUSED(blocklen);
 
-#if defined(__AVX2__)
+#if defined(__AVX2__) && !defined(__APPLE__)
     // Lookup table to convert signed nibbles to signed bytes
     __m256i signextendlut = _mm256_castsi128_si256(_mm_set_epi8(-1, -2, -3, -4, -5, -6, -7, -8, 7, 6, 5, 4, 3, 2, 1, 0));
     signextendlut = _mm256_permute2f128_si256(signextendlut, signextendlut, 0);