rewind must clear the error indicator in addition to seeking

src/stdio/rewind.c

@@ -1,6 +1,9 @@
-#include <stdio.h>
+#include "stdio_impl.h"
 
 void rewind(FILE *f)
 {
-	fseek(f, 0, SEEK_SET);
+	FLOCK(f);
+	__fseeko_unlocked(f, 0, SEEK_SET);
+	f->flags &= ~F_ERR;
+	FUNLOCK(f);
 }