shader: implement 32-bit RDNA2 IMAGE_ATOMIC_CMPSWAP (#952)

* shader: implement 32-bit RDNA2 image atomic compare-and-swap

* shader: share atomic emission and correct image barriers

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Co-authored-by: nmzik <Nmzik@mail.ru>

src/graphics/shader/recompiler/frontend/decode/ShaderDecoder.h

@@ -599,6 +599,7 @@ enum class Opcode {
 	IMAGE_STORE,
 	IMAGE_STORE_MIP,
 	IMAGE_ATOMIC_SWAP,
+	IMAGE_ATOMIC_CMPSWAP,
 	IMAGE_ATOMIC_ADD,
 	IMAGE_ATOMIC_SMIN,
 	IMAGE_ATOMIC_UMIN,