FP2 is not affected by Meltdown, anyway (Krait 400 are based on Cortex A-15, which were not affected).
Spectre is a set of vulnerabilities — most of them yet-to-be-discovered — and “fixing” Spectre will take longer for any vendor (thus its name: “it will haunt us for some time”). Nonetheless, they are difficult to exploit, so install software only from trusted parties (Google Play, F-Droid) and you’ll be covered until mitigations to Spectre arrive, in the next February update.
(Please, continue the discussion in the dedicated FP2 patch for Meltdown/Spectre thread)