Description of problem:
The command:
   mock -r fedora-rawhide-x86_64 --copyin /etc/hosts /etc/hosts
fails with a permissions errror. 


Version-Release number of selected component (if applicable):
Rawhide and F10

How reproducible:
always

Steps to Reproduce:
1. Initialize a chroot (e.g. mock -r fedora-rawhide-x86_64 --init)
2. Try to copy something to /etc in the chroot using --copyin
3. Get permission denyed error
  
Actual results:
Permission denied

Expected results:
Successful copy of file into chroot

Additional info:
This is probably because of the --copyin command dropping privileges before doing the copy. we need to determine if we should keep privleges for copyin operations