Correctly report repaired compliance for commands promises.

For compliance, commands promises are interpreted to have been KEPT
for 0 returns status, and NOTKEPT for non-zero. In order to maintain
compatibility with repaired classes set via body classes, a REPAIRED
state from VerifyCommandRetcode is overwritten with KEPT.

If the body classes also defines return codes for which the compliance
should be REPAIRED, then honour this and don't overwrite with KEPT.

Fixes: #5489