[SYCL] UR enum values are already typed, avoid explicit casts (#18287)
Apparently, `get_info<info::device::opencl_c_version>` was returning
garbage because its `UrCode` is `__SYCL_TRAIT_HANDLED_IN_RT` while no
special handling was in fact done for it. Since it's deprecated anyway
I'm not trying to fix that but just throw an exception instead.
Before this change:
```
$ llvm-lit -a Basic/info.cpp 2>&1 | grep 'OpenCL C version:'
# | OpenCL C version: ^C
# | OpenCL C version: ^D
# | OpenCL C version: ^E
# | OpenCL C version: ^C
$ sycl-ls
[level_zero:gpu][level_zero:0] Intel(R) oneAPI Unified Runtime over Level-Zero, Intel(R) Data Center GPU Max 1550 12.60.7 [1.6.31294.120000]
[level_zero:gpu][level_zero:1] Intel(R) oneAPI Unified Runtime over Level-Zero, Intel(R) Data Center GPU Max 1550 12.60.7 [1.6.31294.120000]
[opencl:fpga][opencl:0] Intel(R) FPGA Emulation Platform for OpenCL(TM), Intel(R) FPGA Emulation Device OpenCL 1.2 [2024.18.10.0.08_160000]
[opencl:cpu][opencl:1] Intel(R) OpenCL, Genuine Intel(R) CPU 0000%@ OpenCL 3.0 (Build 0) [2024.18.10.0.08_160000]
[opencl:gpu][opencl:2] Intel(R) OpenCL Graphics, Intel(R) Data Center GPU Max 1550 OpenCL 3.0 NEO [24.39.31294.12]
[opencl:gpu][opencl:3] Intel(R) OpenCL Graphics, Intel(R) Data Center GPU Max 1550 OpenCL 3.0 NEO [24.39.31294.12]
```