Tidyup: Move HasLoc instances into their own module from compiler/GHC/Iface/Ext/Ast.hs
This is a follow-up from !10743 (closed) which moved the HasLoc
class from compiler/GHC/Iface/Ext/Ast.hs
to compiler/GHC/Parser/Annotation.hs
.
This had the unfortunate effect of introducing orphans in Ast.hs
. Remove the orphan instances, probably by moving the HasLoc
instance into its own module, as discussed in !10743 (comment 508331)