Commit 70b074df4e ("media: fix pdf build with Spinx 1.6") caused
a regression at Sphinx 1.4 PDF build: although it produces a full
document in batch mode, it returns errors on interactive mode:
[63]
Runaway argument?
{\relax
! Paragraph ended before \multicolumn was complete.
<to be read again>
\par
l.7703 \hline\end{tabulary}
The error seems to be due to some bug at Sphinx PDF output:
when multicolumns is used, it doesn't accept an empty string.
Just removing the :cpan:`1` and replacing by two empty
columns fix the issue.
Fixes: 70b074df4e ("media: fix pdf build with Spinx 1.6")
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>