neutron-hostconfig-ovs: add odl-aaa-cert dependency

neutron-hostconfig-ovs: add odl-aaa-cert dependency

odl-neutron-hostconfig-ovs SingleFeatureTest fails with the following
exception to load dependent feature.

> Caused by: java.lang.IllegalArgumentException: null encryptSalt in AaaEncryptServiceConfig: AaaEncryptServiceConfig{augmentations={}}
> 	at org.opendaylight.aaa.encrypt.AAAEncryptionServiceImpl.<init>(AAAEncryptionServiceImpl.java:68)
> 	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
> 	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
> 	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
> 	at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
> 	at org.apache.aries.blueprint.utils.ReflectionUtils.newInstance(ReflectionUtils.java:331)
> 	at org.apache.aries.blueprint.container.BeanRecipe.newInstance(BeanRecipe.java:984)
> 	at org.apache.aries.blueprint.container.BeanRecipe.getInstanceFromType(BeanRecipe.java:349)
> 	... 30 more

Change-Id: I674cdaa1055b7aa3ecc02af485bf744f28101dbe
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>