Update godoc for the default value of logtostderr

godoc says the default value of `logtostderr` is false, which is wrong.

klog.go

@@ -35,11 +35,11 @@
 // Log output is buffered and written periodically using Flush. Programs
 // should call Flush before exiting to guarantee all log output is written.
 //
-// By default, all log statements write to files in a temporary directory.
+// By default, all log statements write to standard error.
 // This package provides several flags that modify this behavior.
 // As a result, flag.Parse must be called before any logging is done.
 //
-//	-logtostderr=false
+//	-logtostderr=true
 //		Logs are written to standard error instead of to files.
 //	-alsologtostderr=false
 //		Logs are written to standard error as well as to files.