po4a/update-po: Disable wrapping in .pot and .po files

po4a/update-po: Disable wrapping in .pot and .po files

The .po files from the Translation Project come with unwrapped
strings so this matches it.

This may reduce the noise in diffs too. When the beginning of
a paragraph had changed, the rest of the lines got rewrapped
in msgsid. Now it's just one very long line that changes when
a paragraph has been edited.

The --add-location=file option was removed as redundant. The line
numbers don't exist in the .pot file due to --porefs file and thus
they cannot get copied to the .po files either.

(cherry picked from commit 4beba1cd62d7f8f7a6f1e899b68292d94c53b599)