This commit updates ghc-tcplugins-extra and hc-typelits-natnormalise
to account for the following minor renaming changes:

   isEqPred          -->  isEqClassPred
   isEqPrimPred      -->  isEqPred
   mkPrimEqPred      -->  mkNomEqPred

from the GHC commit 0225249a43a49e1ef36de14d28a7aadd7c796a95.