media: doc: pixfmt-yuv: Fix 4:4:4 subsampling info

YUV 4:4:4 is not subsampled, fix this in the docs.

Fixes: da785536 ("media: doc: pixfmt-yuv: Move all semi-planar YUV formats to common file")
Signed-off-by: Helen Koike <helen.koike@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst

@@ -396,9 +396,9 @@ number of lines as the luma plane.
 NV24 and NV42
 -------------
 
-Semi-planar YUV 4:4:4 formats. The chroma plane is subsampled by 2 in the
-horizontal direction. Chroma lines contain half the number of pixels and the
-same number of bytes as luma lines, and the chroma plane contains the same
+Semi-planar YUV 4:4:4 formats. The chroma plane is not subsampled.
+Chroma lines contain the same number of pixels and twice the
+number of bytes as luma lines, and the chroma plane contains the same
 number of lines as the luma plane.
 
 .. flat-table:: Sample 4x4 NV24 Image