media: uvcvideo: Limit power line control for Chicony Easycamera

Two different Easycamera devices do not implement the power line control
correctly. Add a corresponding control mapping override.

Bus 001 Device 003: ID 04f2:b6ba Chicony Electronics Co., Ltd EasyCamera
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass          239 Miscellaneous Device
  bDeviceSubClass         2
  bDeviceProtocol         1 Interface Association
  bMaxPacketSize0        64
  idVendor           0x04f2 Chicony Electronics Co., Ltd
  idProduct          0xb6ba
  bcdDevice           10.70
  iManufacturer           3 Chicony Electronics Co.,Ltd.
  iProduct                1 EasyCamera
  iSerial                 2 0001
  bNumConfigurations      1

Bus 001 Device 003: ID 04f2:b746 Chicony Electronics Co., Ltd EasyCamera
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass          239 Miscellaneous Device
  bDeviceSubClass         2
  bDeviceProtocol         1 Interface Association
  bMaxPacketSize0        64
  idVendor           0x04f2 Chicony Electronics Co., Ltd
  idProduct          0xb746
  bcdDevice           97.57
  iManufacturer           3 Chicony Electronics Co.,Ltd.
  iProduct                1 EasyCamera
  iSerial                 2 0001
  bNumConfigurations      1

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>