[libclc] [libclc] Only check the triple architecture for libclc (PR #194149)

[Matt Arsenault via cfe-commits]

arsenm wrote:

PTX should really get down to 1 triple. I'm not sure there's a real ABI difference. If there is, that should be fixed. Languages are not really supposed to be separate ABIs. I'm also not sure anything is really using the PTX support here 

https://github.com/llvm/llvm-project/pull/194149