Delete security groups from Redis

Delete security groups from vif when --no-security-groups is
specified in Redis.

RM10973
Checks for different things. `kwargs = {}` will fail the first check. `kwargs = {"security_groups": []}` will pass the first check, but fail the second check. `kwargs = {"security_groups": ['foo']}` will pass both checks. In other words, the first if statement is checking the key is in the dictionary, the second is checking for a value with that key.