fetch: make set_head() call easier to read

We ignore any error returned from set_head(), but 638060d (fetch
set_head: refactor to use remote directly, 2025-01-26) left its call in
a noop "if" conditional as a sort of note-to-self.

When c834d1a (fetch: only respect followRemoteHEAD with configured
refspecs, 2025-03-18) added a "do_set_head" flag, it was rolled into the
same conditional, putting set_head() on the right-hand side of a
short-circuit AND.

That's not wrong, but it really hides the point of the line, which
is (maybe) calling the function.

Instead, let's have a full if() block for the flag, and then our comment
(with some rewording) will be sufficient to clarify the error handling.

Signed-off-by: Jeff King <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: peff

builtin/fetch.c

@@ -1903,12 +1903,13 @@ static int do_fetch(struct transport *transport,
 				  "you need to specify exactly one branch with the --set-upstream option"));
 		}
 	}
-	if (do_set_head && set_head(remote_refs, transport->remote))
-		;
+	if (do_set_head) {
 		/*
-		 * Way too many cases where this can go wrong
-		 * so let's just fail silently for now.
+		 * Way too many cases where this can go wrong so let's just
+		 * ignore errors and fail silently for now.
 		 */
+		set_head(remote_refs, transport->remote);
+	}
 
 cleanup:
 	if (retcode) {