staging: tegra-video: fix V4L2 dependency

Rather than using a dependency on VIDEO_V4L2, this driver uses
"select", which fails when other dependencies are missing:

WARNING: unmet direct dependencies detected for VIDEO_V4L2
  Depends on [n]: MEDIA_SUPPORT [=y] && (I2C [=y] || I2C [=y]=n) && VIDEO_DEV [=n]
  Selected by [y]:
  - VIDEO_TEGRA [=y] && STAGING [=y] && STAGING_MEDIA [=y] && MEDIA_SUPPORT [=y] && TEGRA_HOST1X [=y]
(plus an endless stream of link errors for other drivers that
depend on VIDEO_V4L2 but are now lacking their dependencies)

Link: https://lore.kernel.org/r/20200527221327.3339232-1-arnd@arndb.de
Fixes: 3d8a97ea ("media: tegra-video: Add Tegra210 Video input driver")
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

drivers/staging/media/tegra-video/Kconfig

@@ -2,7 +2,7 @@
 config VIDEO_TEGRA
 	tristate "NVIDIA Tegra VI driver"
 	depends on TEGRA_HOST1X
-	select VIDEO_V4L2
+	depends on VIDEO_V4L2
 	select MEDIA_CONTROLLER
 	select VIDEOBUF2_DMA_CONTIG
 	help