media: vidtv: don't initialize cnr2qual var

As reported by gcc:

	drivers/media/test-drivers/vidtv/vidtv_demod.c: In function 'vidtv_demod_set_frontend':
	drivers/media/test-drivers/vidtv/vidtv_demod.c:265:42: warning: variable 'cnr2qual' set but not used [-Wunused-but-set-variable]
	  265 |  const struct vidtv_demod_cnr_to_qual_s *cnr2qual = NULL;
	      |                                          ^~~~~~~~

It turns that the var is not needed at all. So, just drop it.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/test-drivers/vidtv/vidtv_demod.c

@@ -73,8 +73,7 @@ static const struct vidtv_demod_cnr_to_qual_s vidtv_demod_t_cnr_2_qual[] = {
 	{ QAM_64, FEC_7_8, 22000, 24000},
 };
 
-static const struct vidtv_demod_cnr_to_qual_s
-	     *vidtv_match_cnr_s(struct dvb_frontend *fe)
+static const struct vidtv_demod_cnr_to_qual_s *vidtv_match_cnr_s(struct dvb_frontend *fe)
 {
 	const struct vidtv_demod_cnr_to_qual_s *cnr2qual = NULL;
 	struct device *dev = fe->dvb->device;
@@ -262,7 +261,6 @@ static int vidtv_demod_get_frontend(struct dvb_frontend *fe,
 
 static int vidtv_demod_set_frontend(struct dvb_frontend *fe)
 {
-	const struct vidtv_demod_cnr_to_qual_s *cnr2qual = NULL;
 	struct vidtv_demod_state *state = fe->demodulator_priv;
 	u32 tuner_status = 0;
 	int ret;
@@ -284,7 +282,6 @@ static int vidtv_demod_set_frontend(struct dvb_frontend *fe)
 						    FE_HAS_SYNC    |
 						    FE_HAS_LOCK	 :
 						    0;
-	cnr2qual = vidtv_match_cnr_s(fe);
 
 	vidtv_demod_update_stats(fe);