Change the way the extra bindings for the generic representation are generated

This ticket serves to record an email conversation in which it was agreed that:

• The extra bindings generated for the generic representation should come from genInst, and not from makeDerivSpecs.

• GHC.Types should not import GHC.Generics; instead, the generic representation for GHC.Types types should be in GHC.Generics (using standalone deriving where necessary).

Trac metadata

Trac field	Value
Version	7.3
Type	Task
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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