[SYCL][UR] Ignore errors in logger callback (#18025)

Fixes #18012 by having the `urLoggerCallback()` ignore messages which
are not warnings as errors should be handled via other mechanisms, i.e.
UR error codes translated into exception messages or by explicitly
enabling logging.

Author: kbenzie

sycl/source/detail/ur.cpp

@@ -79,7 +79,9 @@ ur_code_location_t codeLocationCallback(void *);
 
 void urLoggerCallback([[maybe_unused]] ur_logger_level_t level, const char *msg,
                       [[maybe_unused]] void *userData) {
-  std::cerr << msg << std::endl;
+  if (level == UR_LOGGER_LEVEL_WARN) {
+    std::cerr << msg << std::endl;
+  }
 }
 
 namespace ur {