vulkan: compile a test shader in cmake to check for coopmat2 support (#10713)

ggml/src/ggml-vulkan/vulkan-shaders/test_coopmat2_support.comp

@@ -0,0 +1,7 @@
+#version 460
+
+#extension GL_NV_cooperative_matrix2 : require
+
+void main()
+{
+}