[media] dev-rds.rst: adjust table dimentions for LaTeX

One of the tables has wrong column dimentions. Fix it.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

Documentation/media/uapi/v4l/dev-rds.rst

@@ -170,7 +170,7 @@ RDS datastructures
 
 .. _v4l2-rds-block-codes:
 
-.. tabularcolumns:: |p{2.2cm}|p{2.2cm}|p{2.2cm}|p{10.9cm}|
+.. tabularcolumns:: |p{5.6cm}|p{2.0cm}|p{1.5cm}|p{7.0cm}|
 
 .. flat-table:: Block defines
     :header-rows:  0