[NFC][libclc] Merge atomic extension built-ins with identical name into a single file (#134489)

llvm-diff shows there is no change to amdgcn--amdhsa.bc.

Similar to how cl_khr_fp64 and cl_khr_fp16 implementations are put in a
same file for math built-ins, this PR do the same to atom_* built-ins.

The main motivation is to prevent that two files with same base name
implementats different built-ins. In a follow-up PR, I'd like to relax
libclc_configure_lib_source to only compare filename instead of path for
overriding, since in our downstream the same category of built-ins, e.g.
math, are organized in several different folders.

0 files changed, 0 insertions, 0 deletions