Fix keymgr key init bug

Fix keymgr key init bug

The 'keymgr_key_init()' function initializes key states if they have
not been set previously. It looks at the key timing metadata and
determines using the given times whether a state should be set to
RUMOURED or OMNIPRESENT.

However, the DNSKEY and ZRRSIG states were mixed up: When looking
at the Activate timing metadata we should set the ZRRSIG state, and
when looking at the Published timing metadata we should set the
DNSKEY state.