Choose version of IntelSycl compiler based on whether dpcpp occurs in CMAKE_CXX_COMPILER

Author: oleksandr-pavlyk

dpctl-capi/CMakeLists.txt

@@ -36,10 +36,10 @@ option(DPCTL_BUILD_CAPI_TESTS
 )
 
 # Minimum version requirement only when oneAPI dpcpp is used.
-if(DPCTL_CUSTOM_DPCPP_INSTALL_DIR)
-    find_package(IntelSycl REQUIRED)
-else()
+if("{CMAKE_CXX_COMPILER}" MATCHES "dpcpp")
     find_package(IntelSycl 2021.2.0 REQUIRED)
+else()
+    find_package(IntelSycl REQUIRED)
 endif()
 
 if(DPCTL_ENABLE_LO_PROGRAM_CREATION)