[clang] [HIP] change default offload archs (PR #139281)

[Matt Arsenault via cfe-commits]

arsenm wrote:

> It seems that the sample program ran without crashing, but the kernel function was never actually executed. You can catch an "invalid device function" error if you call `HIP_CHECK(hipGetLastError())` at the start of main.
> 

Lack of proper error checking in the host APIs or host API usage isn't really a problem we solve here. Anything like a system call should be always checked for failure.

https://github.com/llvm/llvm-project/pull/139281