[sycl-post-link] Split SYCL and ESIMD kernels into separate modules (#3044)
* [sycl-post-link] Split SYCL and ESIMD kernels into separate modules
Enabled via a new option - '-split-esimd'.
For now this change doesn't have any effect on existing programs
since we don't allow mixing SYCL and ESIMD kernels in one source
or in one program.
But this is an essential step towards this goal since ESIMD
kernels require specific processing as opposed to usual SYCL
kernels.