media: dvb-usb: fix wrong definition

syzbot reported WARNING in vmalloc. The problem
was in sizo size passed to vmalloc.

The root case was in wrong cxusb_bluebird_lgz201_properties
defenition. adapter array has only 1 entry, but num_adapters was
2.

Call Trace:
 __vmalloc_node mm/vmalloc.c:2963 [inline]
 vmalloc+0x67/0x80 mm/vmalloc.c:2996
 dvb_dmx_init+0xe4/0xb90 drivers/media/dvb-core/dvb_demux.c:1251
 dvb_usb_adapter_dvb_init+0x564/0x860 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:184
 dvb_usb_adapter_init drivers/media/usb/dvb-usb/dvb-usb-init.c:86 [inline]
 dvb_usb_init drivers/media/usb/dvb-usb/dvb-usb-init.c:184 [inline]
 dvb_usb_device_init.cold+0xc94/0x146e drivers/media/usb/dvb-usb/dvb-usb-init.c:308
 cxusb_probe+0x159/0x5e0 drivers/media/usb/dvb-usb/cxusb.c:1634

Reported-by: syzbot+7336195c02c1bd2f64e1@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Change-Id: I946d6a4b1a1d43fc3148f556122a2106194c1ad2
diff --git a/drivers/media/usb/dvb-usb/cxusb.c b/drivers/media/usb/dvb-usb/cxusb.c
index 761992a..7707de7 100644
--- a/drivers/media/usb/dvb-usb/cxusb.c
+++ b/drivers/media/usb/dvb-usb/cxusb.c
@@ -1947,7 +1947,7 @@
 
 	.size_of_priv     = sizeof(struct cxusb_state),
 
-	.num_adapters = 2,
+	.num_adapters = 1,
 	.adapter = {
 		{
 		.num_frontends = 1,