lib/commonio.c: Use uintmax_t to print nlink_t

See uintmax_t(3type).

While at it, remove the useless cast to (void).

Signed-off-by: Alejandro Colomar <alx@kernel.org>

lib/commonio.c

@@ -110,9 +110,9 @@ static int check_link_count (const char *file, bool log)
 
 	if (sb.st_nlink != 2) {
 		if (log) {
-			(void) fprintf (shadow_logfd,
-			                "%s: %s: lock file already used (nlink: %u)\n",
-			                shadow_progname, file, sb.st_nlink);
+			fprintf(shadow_logfd,
+			        "%s: %s: lock file already used (nlink: %ju)\n",
+			        shadow_progname, file, (uintmax_t) sb.st_nlink);
 		}
 		return 0;
 	}