SPV: Don't decorate locations within an array, it doesn't make sense.

This fixes issue #360.

Test/spv.450.tesc

@@ -0,0 +1,20 @@
+#version 450 core
+
+layout(vertices = 4) out;
+
+patch out vec4 patchOut;
+
+struct S {
+    float sMem1;  // should not see a patch decoration
+    float sMem2;  // should not see a patch decoration
+};
+
+layout(location = 12) patch out TheBlock {
+    highp float bMem1;  // should not see a location decoration
+    highp float bMem2;
+    S s;                // should see a patch decoration
+} tcBlock[2];
+
+void main()
+{
+}