[clang] Enable offloadlib option in SYCL and CL mode (PR #162980)

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jinge90 wrote:

> @jinge90, I don't think the title accurately describes what the patch does.
> 
> I see that you enabled `--[no-]offloadlib` flags for MSVC compatible driver. The only SYCL related change is the help message. Did you intend to put more changes in this PR?
> 
> Please, add a test for using `--[no-]offloadlib` in CL compatibility mode.

Hi, @bader 
I don't have more changes in this PR. The sycl toolchain can be invoked via CL compatibility mode in driver, so I enable this option in CL compatibility mode.

Thanks very much.

https://github.com/llvm/llvm-project/pull/162980