HexFloatLiterals doesn't parse for unboxed Float# and Double# literals
In ghc 9.4.2 (reproduced in both ghci and ghc single-file mode)
Test.hs:
```
{-# language HexFloatLiterals, MagicHash #-}
module Test where
import GHC.Types
a = D# 0x1p0##
```
complains
```
Test.hs:6:1: error:
parse error (possibly incorrect indentation or mismatched brackets)
```
but replacing it with `a = D# 1.0##` or `a = 0x1p0 :: Double` is fine.
Similarly for floats.
issue