Fix a comment

Author: Zoxc

config.toml.example

@@ -317,7 +317,7 @@
 # Whether to always use incremental compilation when building rustc
 #incremental = false
 
-# Build rustc with experimental parallelization
+# Build a multi-threaded rustc
 #parallel-compiler = false
 
 # The default linker that will be hard-coded into the generated compiler for