[llvm] [Offload][Lang] Add internal StreamTy (PR #216374)

[Sophia Herrmann via llvm-commits]

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@@ -27,6 +28,15 @@ using namespace offload;
 // Weak so another runtime object can override the default stream mode.
 __attribute__((weak)) uint32_t PerThreadQueue = 0;
 
+static constexpr ol_error_struct_t InvalidNullPointerError = {
+    OL_ERRC_INVALID_NULL_POINTER, "invalid null stream pointer"};
+
+static constexpr ol_error_struct_t InvalidDeviceError = {OL_ERRC_INVALID_DEVICE,
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jellytabby wrote:

Moved into a new header `OffloadErrors.h`

https://github.com/llvm/llvm-project/pull/216374