[SYCL] Allow "=" sign as part of value in LIT_EXTRA_ENVIRONMENT key/value pairs (#1614)

Author: aelovikov-intel

SYCL/lit.cfg.py

@@ -83,7 +83,7 @@
 if config.extra_environment:
     lit_config.note("Extra environment variables")
     for env_pair in config.extra_environment.split(','):
-        [var,val]=env_pair.split("=")
+        [var,val]=env_pair.split("=", 1)
         if val:
            llvm_config.with_environment(var,val,append_path=True)
            lit_config.note("\t"+var+"="+val)