texinfo: Avoid a problem with a dependency on perl(Locale::gettext_xs)

texinfo: Avoid a problem with a dependency on perl(Locale::gettext_xs)

We do not build the Locale::gettext_xs Perl module and the code will
test for it and happily use Locale::gettext_pp instead if it is not
found. However, this still causes a file dependency on
perl(Locale::gettext_xs) to be generated, which must be satisfied by
adding an explicit provide for it.

Signed-off-by: Peter Kjellerstedt <peter.kjellerstedt@axis.com>
Signed-off-by: Mark Hatle <mark.hatle@windriver.com>