[media] dvb-frontends: fix potential NULL pointer dereference in stv0900_set_mclk()

The dereference should be moved below the NULL test.
dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/dvb-frontends/stv0900_core.c

@@ -300,15 +300,15 @@ static enum fe_stv0900_error stv0900_set_mclk(struct stv0900_internal *intp, u32
 {
 	u32 m_div, clk_sel;
 
-	dprintk("%s: Mclk set to %d, Quartz = %d\n", __func__, mclk,
-			intp->quartz);
-
 	if (intp == NULL)
 		return STV0900_INVALID_HANDLE;
 
 	if (intp->errs)
 		return STV0900_I2C_ERROR;
 
+	dprintk("%s: Mclk set to %d, Quartz = %d\n", __func__, mclk,
+			intp->quartz);
+
 	clk_sel = ((stv0900_get_bits(intp, F0900_SELX1RATIO) == 1) ? 4 : 6);
 	m_div = ((clk_sel * mclk) / intp->quartz) - 1;
 	stv0900_write_bits(intp, F0900_M_DIV, m_div);