Increase logging verbosity as to what exactly hit a limit

Increase logging verbosity as to what exactly hit a limit

rpki-client: https://testbed.krill.cloud/rrdp/notification.xml: pulling from network
rpki-client: https://testbed.krill.cloud/rrdp/notification.xml: downloading snapshot (bfb0a57e-d16b-44a1-9502-f15b4bc1ce1a#110135)
rpki-client: parse failed, snapshot element for rsync://testbed.krill.cloud/repo/testbed/0/DDAF321520EE4817D716FA047FC05FE2934204DB.crl too big
rpki-client: https://testbed.krill.cloud/rrdp/notification.xml: parse error at line 135: parsing aborted
rpki-client: https://testbed.krill.cloud/rrdp/notification.xml: load from network failed, fallback to rsync

OK tb@ claudio@