Fix logging flags documentation to refer to `LogSink`s instead of logfiles

PiperOrigin-RevId: 568603611
Change-Id: I7a31e0d6336a7235a8dc6eeed5680625cb3b4298

absl/log/internal/flags.h

@@ -33,7 +33,7 @@
 // !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 // !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 
 
 // Log messages at this severity or above are sent to stderr in *addition* to
 // Log messages at this severity or above are sent to stderr in *addition* to
-// logfiles.  Defaults to `ERROR`.  See log_severity.h for numeric values of
+// `LogSink`s.  Defaults to `ERROR`.  See log_severity.h for numeric values of
 // severity levels.
 // severity levels.
 ABSL_DECLARE_FLAG(int, stderrthreshold);
 ABSL_DECLARE_FLAG(int, stderrthreshold);