Merge branch 'rs/strbuf-getwholeline-fix' into maint

A helper function to read a single whole line into strbuf
mistakenly triggered OOM error at EOF under certain conditions,
which has been fixed.

* rs/strbuf-getwholeline-fix:
  strbuf: clear errno before calling getdelim(3)

strbuf.c

@@ -476,6 +476,7 @@ int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 	/* Translate slopbuf to NULL, as we cannot call realloc on it */
 	if (!sb->alloc)
 		sb->buf = NULL;
+	errno = 0;
 	r = getdelim(&sb->buf, &sb->alloc, term, fp);
 
 	if (r > 0) {