Linstor: Refactor resource creation methods to LinstorUtil

Move reusable methods from LinstorPrimaryDataStoreDriverImpl to LinstorUtil
to enable sharing with other components:
- logLinstorAnswer, logLinstorAnswers, checkLinstorAnswersThrow
- getRscGrp, getEncryptedLayerList, applyQoSSettings
- createResourceBase, createResource, spawnResource
- canShareTemplateForResourceGroup, foundShareableTemplate

Add LIN_PROP_DRBDOPT_EXACT_SIZE constant and exactSize parameter support
for DRBD exact-size property handling during resource creation.

Author: rp-