Remove invitation to report a bug about unknown encoding

The error message when we couldn't determine the encoding from a locale
said to report a bug about that.  That might have been appropriate when
this code was first added, but by now this works pretty solidly and any
encodings we don't recognize we probably just don't support.  We still
print the warning, but no longer invite the bug report.

src/port/chklocale.c

@@ -290,8 +290,7 @@ pg_codepage_to_encoding(UINT cp)
 			return encoding_match_list[i].pg_enc_code;
 
 	ereport(WARNING,
-			(errmsg("could not determine encoding for codeset \"%s\"", sys),
-		   errdetail("Please report this to <pgsql-bugs@postgresql.org>.")));
+			(errmsg("could not determine encoding for codeset \"%s\"", sys)));
 
 	return -1;
 }
@@ -419,8 +418,7 @@ pg_get_encoding_from_locale(const char *ctype, bool write_message)
 #else
 		ereport(WARNING,
 				(errmsg("could not determine encoding for locale \"%s\": codeset is \"%s\"",
-						ctype, sys),
-		   errdetail("Please report this to <pgsql-bugs@postgresql.org>.")));
+						ctype, sys)));
 #endif
 	}