vulkan: disable mmvq on Intel Windows driver (ggml-org#20672)

* vulkan: disable mmvq on Intel Windows driver

* improve comment

Author: 0cc4m

ggml/src/ggml-vulkan/ggml-vulkan.cpp

@@ -7646,20 +7646,14 @@ static bool ggml_vk_should_use_mmvq(const vk_device& device, uint32_t m, uint32_
             return true;
         }
     case VK_VENDOR_ID_INTEL:
-        if (k < 2048) {
+        if (device->driver_id == vk::DriverId::eIntelProprietaryWindows) {
+            // Intel Windows proprietary driver MMVQ performance is worse than fp16, see
+            // https://github.com/ggml-org/llama.cpp/issues/17628
             return false;
         }
 
-        if (device->driver_id == vk::DriverId::eIntelProprietaryWindows) {
-            // Intel Windows proprietary driver tuning
-            switch (src0_type) {
-            case GGML_TYPE_MXFP4:
-            case GGML_TYPE_Q4_K:
-            case GGML_TYPE_Q5_K:
-                return false;
-            default:
-                return true;
-            }
+        if (k < 2048) {
+            return false;
         }
 
         switch (src0_type) {