[Coverity][UR][L0] unchecked return value

[AlexeySachkov]

See Coverity issues at https://scan.coverity.com/projects/intel-llvm?tab=overview

CID 527591:

llvm/unified-runtime/source/adapters/level_zero/image_common.cpp

Line 778 in c310aed

ur2zeImageDesc(pSrcImageFormat, pSrcImageDesc, zeSrcImageDesc);

CID 527599

llvm/unified-runtime/source/adapters/level_zero/memory.cpp

Lines 1388 to 1389 in c310aed

	Queue->executeCommandList(CommandList, false /*IsBlocking*/,
	false /*OKToBatchCommand*/);