CUDA: fix logic for V100 + GGML_CUDA_FORCE_MMQ (#12098)

Author: JohannesGaessler

ggml/src/ggml-cuda/mmq.cuh

@@ -109,9 +109,9 @@ static constexpr __device__ int get_mmq_x_max_device() {
 
 #if __CUDA_ARCH__ >= GGML_CUDA_CC_VOLTA
 #ifdef GGML_CUDA_FORCE_MMQ
-    return MMQ_DP4A_MAX_BATCH_SIZE;
-#else // GGML_CUDA_FORCE_MMQ
     return 128;
+#else // GGML_CUDA_FORCE_MMQ
+    return MMQ_DP4A_MAX_BATCH_SIZE;
 #endif // GGML_CUDA_FORCE_MMQ
 #else // __CUDA_ARCH__ >= GGML_CUDA_CC_VOLTA