fix: SDO service

[whoTBecker]

Abort sdo download request if size exceeds allowed length.
Only accept ca download if size matches.
Fix complete access of bit data types.
Allow ca access for objects with flexible length.
Correct validation of sdo segmented request.
Serve correct datatype for SDO get object description.
Correct size limit for complete access.

(Also included: Pull-Request #194 and #197 )

[nakarlsson]

Can you guys please squash functional commits + fixes tied to functional commits? Would make life easier for us to review.
Otherwise we need double check possible issues with later commits that might include fixes.

thanks

[CLAassistant]

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0 out of 3 committers have signed the CLA.

❌ whoMBadura
❌ whoTBecker
❌ ule29147
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