pointercal-xinput: Mark as SIGGEN_EXCLUDERECIPES_ABISAFE
When including xinput-calibrator, in commit "xinput-calibrator: move
it from meta-oe to oe-core" the pointercal-xinput has not been added
to the SIGGEN_EXCLUDERECIPES_ABISAFE. This changes adds it to the
meta/conf/layer.conf's file list.
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>