[clang] [llvm] [clang][RISCV] Change default abi with f extension but without d extension (PR #73489)

[Ben Shi via cfe-commits]

benshi001 wrote:

I think this is reasonable, even I myself made such a change months ago in Phabracator, but finally not approved. 

https://github.com/llvm/llvm-project/pull/73489