libweston: fix major in libweston.pc

Renames forgotten in "libweston: use new versioning scheme".

Cc: Emil Velikov <emil.velikov@collabora.com>
Cc: Quentin Glidic <sardemff7+git@sardemff7.net>
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
Reviewed-by: Quentin Glidic <sardemff7+git@sardemff7.net>
1 file changed