[media] dib7000p: fix sparse warning

drivers/media/dvb-frontends/dib7000p.c:2562:5: warning: symbol 'dib7090_set_diversity_in' was not declared. Should it be static?
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/dvb-frontends/dib7000p.c

@@ -2559,7 +2559,7 @@ static void dib7090_setHostBusMux(struct dib7000p_state *state, int mode)
 	dib7000p_write_word(state, 1288, reg_1288);
 }
 
-int dib7090_set_diversity_in(struct dvb_frontend *fe, int onoff)
+static int dib7090_set_diversity_in(struct dvb_frontend *fe, int onoff)
 {
 	struct dib7000p_state *state = fe->demodulator_priv;
 	u16 reg_1287;