media: atomisp: auto-select VIDEO_V4L2_SUBDEV_API

VIDEO_ATOMISP depends on VIDEO_V4L2_SUBDEV_API, if VIDEO_V4L2_SUBDEV_API
 is not selected, it will cause compilation error

drivers/staging/media/atomisp/pci/atomisp_cmd.c:6079:42: error:
 ‘struct v4l2_subdev_fh’ has no member named ‘pad’ atomisp_subdev_set_ffmt
(&asd->subdev, fh.pad, V4L2_SUBDEV_FORMAT_ACTIVE,

add auto select VIDEO_V4L2_SUBDEV_API if VIDEO_ATOMISP is selected

Link: https://lore.kernel.org/linux-media/20210210033830.961086-1-ztong0001@gmail.comSigned-off-by: Tong Zhang <ztong0001@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/staging/media/atomisp/Kconfig

@@ -15,6 +15,7 @@ config VIDEO_ATOMISP
 	depends on PMIC_OPREGION
 	select IOSF_MBI
 	select VIDEOBUF_VMALLOC
+	select VIDEO_V4L2_SUBDEV_API
 	help
 	  Say Y here if your platform supports Intel Atom SoC
 	  camera imaging subsystem.