Remove unnecessary xxSys dependencies

Cherry-picked from !265 (merged) to 2018-patches

(cherry picked from commit 996b59d8)

728535ce Merge branch 'removeLbcomSysDependency' into 'master'

• [2018-10-30 00:14] Validation started with lhcb-2018-patches#382

merged

mentioned in commit aa5e2f49