sshbuf_peek_u8
ASSERT_INT_EQ(sshbuf_peek_u8(p1, 0, &v8), 0);
ASSERT_INT_EQ(sshbuf_peek_u8(p1, 9, &v8), 0);
ASSERT_INT_EQ(sshbuf_peek_u8(p1, sizeof(x), &v8),
ASSERT_INT_EQ(sshbuf_peek_u8(p1, 1000, &v8),
int sshbuf_peek_u8(const struct sshbuf *buf, size_t offset,