[SYCL][L0] Fix memory leak in PiDeviceCache and ZeCommandList (#2974)
Release resources in pi_platforms and pi_devices while tearing down.
Upon tear-down, platforms are destroyed.
Each platform contains a piDeviceCache.
When destroying each pi_platform, we have to destroy zeCommandList, too.
Signed-off-by: Byoungro So byoungro.so@intel.com