[ROCM] enable matmul(dot) and others (#391)

include/triton/driver/dispatch.h

@@ -11,7 +11,6 @@
 #include "triton/external/CUDA/nvml.h"
 
 //// HIP backend
-//#define __HIP_PLATFORM_AMD__
 #include "triton/external/hip.h"
 
 //Exceptions

include/triton/ir/builder.h

@@ -42,6 +42,7 @@ public:
   value *get_int64(int64_t val);
   value *get_float16(float val);
   value *get_float32(float val);
+  value *get_float64(float val);
   value *get_range(int32_t lo, int32_t hi);
   // Types
   type *get_void_ty();