[media] em28xx-dvb: don't initialize drx-d non-used fields with zero

There's no need to initialize unused fields with zero, as Kernel does
it automatically.

Removing the initialization makes the code cleaner.

This also allows the removal of the unused pll_set callback.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/em28xx/em28xx-dvb.c

@@ -303,10 +303,12 @@ static struct zl10353_config em28xx_zl10353_xc3028_no_i2c_gate = {
 };
 
 static struct drxd_config em28xx_drxd = {
-	.index = 0, .demod_address = 0x70, .demod_revision = 0xa2,
-	.demoda_address = 0x00, .pll_address = 0x00,
-	.pll_type = DRXD_PLL_NONE, .clock = 12000, .insert_rs_byte = 1,
-	.pll_set = NULL, .osc_deviation = NULL, .IF = 42800000,
+	.demod_address = 0x70,
+	.demod_revision = 0xa2,
+	.pll_type = DRXD_PLL_NONE,
+	.clock = 12000,
+	.insert_rs_byte = 1,
+	.IF = 42800000,
 	.disable_i2c_gate_ctrl = 1,
 };