V4L/DVB (7704): pvrusb2: Fix slop involving use of struct which might not be defined

When the DVB interface is not compiled, the pvr2_dvb_props struct is
not available - so it really should be ifdef'ed out as well.  This
didn't cause an error because in this context its usage was as an
opaque pointer.  But it really shouldn't be present at all if DVB is
not enabled.
Signed-off-by: NMike Isely <isely@pobox.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/video/pvrusb2/pvrusb2-devattr.h

@@ -68,9 +68,11 @@ struct pvr2_device_desc {
 	   was initialized from internal ROM. */
 	struct pvr2_string_table fx2_firmware;
 
+#ifdef CONFIG_VIDEO_PVRUSB2_DVB
 	/* callback functions to handle attachment of digital tuner & demod */
 	struct pvr2_dvb_props *dvb_props;
 
+#endif
 	/* Initial standard bits to use for this device, if not zero.
 	   Anything set here is also implied as an available standard.
 	   Note: This is ignored if overridden on the module load line via