libatasmart: fix QA warnings

fix the following warnings:
WARNING: For recipe libatasmart, the following files/directories were installed but not shipped in any package:
WARNING:   /usr/share/vala
WARNING:   /usr/share/vala/vapi
WARNING:   /usr/share/vala/vapi/atasmart.vapi

Signed-off-by: Andreas Müller <schnitzeltony@googlemail.com>
Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>