Code quality: Fix header guards consistency

Adds `header_guards.sh` bash script, used in CI to validate future
changes. Can be run locally to fix invalid header guards.

drivers/vulkan/vulkan_context.h

@@ -330,4 +330,4 @@ public:
 	virtual ~VulkanContext();
 };
 
-#endif // VULKAN_DEVICE_H
+#endif // VULKAN_CONTEXT_H

drivers/vulkan/vulkan_hooks.h

@@ -45,4 +45,4 @@ public:
 	virtual ~VulkanHooks(){};
 };
 
-#endif
+#endif // VULKAN_HOOKS_H