[SYCL] Fix Windows build configure issue

[pvchupin]

Error: "Threads::Threads" but the target was not found. Perhaps a
find_package() call is missing for an IMPORTED target, or an ALIAS
target is missing?

[yanfeng3721]

Hi @pvchupin @smaslov-intel , the PR will break RHEL Linux nightly build.
Pre commit test log: http://icl-jenkins2.sc.intel.com:8080/blue/organizations/jenkins/SYCL_CI%2Fintel%2FPrecommit_Check_User/detail/Precommit_Check_User/1637/pipeline/91.

[2022-04-26T03:02:57.789Z] [2754/2874] Linking CXX shared library lib/libpi_level_zero.so

[2022-04-26T03:02:57.789Z] FAILED: lib/libpi_level_zero.so 

[2022-04-26T03:02:57.789Z] : && /rdrive/ref/gcc/7.3.0/rhel70/efi2/bin/g++ -fPIC -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wno-missing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wno-maybe-uninitialized -Wno-noexcept-type -Wdelete-non-virtual-dtor -Wno-comment -Wmisleading-indentation -fdiagnostics-color -ffunction-sections -fdata-sections -Wall -Wextra -Wno-deprecated-declarations -Werror -O3 -DNDEBUG  -Wl,-z,defs -Wl,-z,nodelete -shared -Wl,-soname,libpi_level_zero.so -o lib/libpi_level_zero.so tools/sycl/plugins/level_zero/CMakeFiles/pi_level_zero.dir/pi_level_zero.cpp.o tools/sycl/plugins/level_zero/CMakeFiles/pi_level_zero.dir/usm_allocator.cpp.o tools/sycl/plugins/level_zero/CMakeFiles/pi_level_zero.dir/tracing.cpp.o tools/sycl/plugins/level_zero/CMakeFiles/pi_level_zero.dir/netbatch/donb3720232_00/runDir/jenkins-dir/workspace/SYCL_CI/intel/Build_PR_RHEL/llvm.src/xpti/src/xpti_proxy.cpp.o -L/netbatch/donb3720232_00/runDir/jenkins-dir/workspace/SYCL_CI/intel/Build_PR_RHEL/llvm.obj/./lib -Wl,-rpath,/netbatch/donb3720232_00/runDir/jenkins-dir/workspace/SYCL_CI/intel/Build_PR_RHEL/llvm.obj/./lib: -lze_loader -Wl,--version-script=/netbatch/donb3720232_00/runDir/jenkins-dir/workspace/SYCL_CI/intel/Build_PR_RHEL/llvm.src/sycl/plugins/ld-version-script.txt -lgcc_s -lgcc -ldl && :

[2022-04-26T03:02:57.789Z] tools/sycl/plugins/level_zero/CMakeFiles/pi_level_zero.dir/pi_level_zero.cpp.o: In function `_ZSt12__apply_implIZNSt11scoped_lockIJSt11shared_lockI15pi_shared_mutexES2_EED4EvEUlRS3_RS2_E_RSt5tupleIJS5_S6_EEJLm0ELm1EEEDcOT_OT0_St16integer_sequenceImJXspT1_EEE.isra.252':

[2022-04-26T03:02:57.789Z] pi_level_zero.cpp:(.text.unlikely._ZSt12__apply_implIZNSt11scoped_lockIJSt11shared_lockI15pi_shared_mutexES2_EED4EvEUlRS3_RS2_E_RSt5tupleIJS5_S6_EEJLm0ELm1EEEDcOT_OT0_St16integer_sequenceImJXspT1_EEE.isra.252+0x2a): undefined reference to `pthread_rwlock_unlock'

[2022-04-26T03:02:57.789Z] pi_level_zero.cpp:(.text.unlikely._ZSt12__apply_implIZNSt11scoped_lockIJSt11shared_lockI15pi_shared_mutexES2_EED4EvEUlRS3_RS2_E_RSt5tupleIJS5_S6_EEJLm0ELm1EEEDcOT_OT0_St16integer_sequenceImJXspT1_EEE.isra.252+0x62): undefined reference to `pthread_rwlock_unlock'

[smaslov-intel]

Fix is coming in #6059