Device code not split in modules when using aspect::atomic64

[Alcpz]

#12673 enabled tests for the opencl:fpga backend, which don't support 64bit atomics.
The following tests,

syclcompat/atomic/atomic_arith.cpp
syclcompat/atomic/atomic_comp_exchange.cpp

failed with the following output:

# .---command stderr------------
# | terminate called after throwing an instance of 'sycl::_V1::compile_program_error'
# |   what():  The program was built for 1 devices
# | Build program log for 'Intel(R) FPGA Emulation Device':
# | Compilation started
# | Unsupported SPIR-V module
# | int 64bit atomics are not supported on FPGA emulator.
# | Compilation failed
# |  -11 (PI_ERROR_BUILD_PROGRAM_FAILURE)
# `-----------------------------
# error: command failed with exit status: -6

The issue is avoided by adding per_kernel split to the tests (-fsycl-device-code-split=per_kernel), which indicates that kernels using atomic64 are not being split into a separate module.

According to #12673 (comment), adding the flag shouldn't be necessary.
#12673 (comment) provides additional context.

To Reproduce

Run syclcompat/atomic/atomic_arith.cpp or syclcompat/atomic/atomic_comp_exchange.cpp sycl-e2e tests using the opencl:fpga or opencl:acc backends.

Environment:

• OS: Linux
• Target device and vendor: OpenCL FPGA
• DPC++ version: intel/llvm 73d3473