shortlog: rename parse_stdin_ident()

This function is actually useful for parsing any identity, whether from
stdin or not. We'll need it for handling trailers.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin/shortlog.c b/builtin/shortlog.c
index d2d8103..e6f4fae 100644
--- a/builtin/shortlog.c
+++ b/builtin/shortlog.c
@@ -98,8 +98,8 @@
 	}
 }
 
-static int parse_stdin_ident(struct shortlog *log,
-			     struct strbuf *out, const char *in)
+static int parse_ident(struct shortlog *log,
+		       struct strbuf *out, const char *in)
 {
 	const char *mailbuf, *namebuf;
 	size_t namelen, maillen;
@@ -156,7 +156,7 @@
 			; /* discard blanks */
 
 		strbuf_reset(&mapped_ident);
-		if (parse_stdin_ident(log, &mapped_ident, v) < 0)
+		if (parse_ident(log, &mapped_ident, v) < 0)
 			continue;
 
 		insert_one_record(log, mapped_ident.buf, oneline.buf);