tuna: Move get_policy_and_rtprio call to parser level

Due to the implementation of the parser for the priority action,
the valid policy and rtprio input can be checked at the parser level.

Call get_policy_and_rtprio on `priority` and `run --priority` commands
at argparse level.

Signed-off-by: Leah Leshchinsky <lleshchi@redhat.com>
Signed-off-by: John Kacur <jkacur@redhat.com>
2 files changed