No it is not; although I believe that a feature request for this feature exists if you want to contact your SE and have them add your vote to that Feature Request. Since your internal DNS servers don't have any clue about GlobalProtect you currently won't receive a DNS entry for clients connected to GlobalProtect.
Click Accept as Solution to acknowledge that the answer to your question has been provided.
The button appears next to the replies on topics you’ve started. The member who gave the solution and all future visitors to this topic will appreciate it!
These simple actions take just seconds of your time, but go a long way in showing appreciation for community members and the LIVEcommunity as a whole!
The LIVEcommunity thanks you for your participation!