layers: Fix Graphics Pipeline pointers not ignored

Some VkGraphicsPipelineCreateInfo pointers must be ignored under some
conditions, but were not in the layers.

Add relevant tests.

Fix tests found broken (using depth or color without attachment in
subpass)
diff --git a/scripts/parameter_validation_generator.py b/scripts/parameter_validation_generator.py
index 9c673fc..ba825e2 100644
--- a/scripts/parameter_validation_generator.py
+++ b/scripts/parameter_validation_generator.py
@@ -154,6 +154,8 @@
             'vkCreateDebugReportCallbackEXT',
             'vkDestroyDebugReportCallbackEXT',
             'vkCreateCommandPool',
+            'vkCreateRenderPass',
+            'vkDestroyRenderPass',
             ]
         # Structure fields to ignore
         self.structMemberBlacklist = { 'VkWriteDescriptorSet' : ['dstSet'] }