[SYCL][PI/CL] check device version/extensions rather than platform version/extensions

[dakr]

For OpenCL backends currently piProgramCreate() queries the platform version (CL_PLATFORM_VERSION) and platform extensions (CL_PLATFORM_EXTENSIONS) to check whether we're capable of running on top of a particular OpenCL backend.

However, there might be platforms where the supported device version is lower than the platform version or where not all devices do support the same extensions and hence some extensions supported by a particular device are not reported in the platform extensions.

In particular for CL_PLATFORM_EXTENSIONS the OpenCL specification says: "[...] Each extension that is supported by all devices associated with this platform must be reported here."

In 3.4.1 Mixed Version Support the specification also says: "[...] The version returned corresponds to the highest version of the OpenCL specification for which the device is conformant, but is not higher than the platform version."

Hence, check for the device version and extensions rather than the platform version and extensions in piProgramCreate().