What's the relation between Germanic adjectival/adverbial suffixes
-ly, -lich, -lijk, ...
and Turkic suffixes
-lik -liq
that convert nouns/adjectives to nouns
Duden and other sources state that -lich is a grammaticalized form of the Middle High German līch ["body"] (which also gave rise to Leiche). -ly, -lich, -lijk (and Scandinavian forms) are actually all of similar derivation and converge to a single Germanic ancestral suffix (see discussion on details here).
The Turkic -lik appeared already in the Old Turkic times and probably was related to a similar in form and meaning Mongolian suffix (see e.g. here).
So, a hypothesis about common ancestry of the Germanic and the Turkic suffixes via borrowing is at least non-parsimonious. (Not to mention, that there are no genetic links between these two groups of languages.)