Generate an enum that supports Bits instances

First of all let me apologize if this is not the correct place to post (as my issue is a priori not with the c2hs software).
I have a TcpState data structure generated by c2hs via `{#enum TCP_ESTABLISHED as TcpState {underscoreToCase} deriving (Eq, Show)#}`.
which generates (from the linux headers)
```
data TcpState = TcpEstablished
| TcpSynSent
| TcpSynRecv
| TcpFinWait1
| TcpFinWait2
| TcpTimeWait
| TcpClose
| TcpCloseWait
| TcpLastAck
| TcpListen
| TcpClosing
| TcpNewSynRecv
| TcpMaxStates
deriving (Eq,Show)
instance Enum TcpState where
succ TcpEstablished = TcpSynSent
succ TcpSynSent = TcpSynRecv
succ TcpSynRecv = TcpFinWait1
succ TcpFinWait1 = TcpFinWait2
succ TcpFinWait2 = TcpTimeWait
succ TcpTimeWait = TcpClose
succ TcpClose = TcpCloseWait
succ TcpCloseWait = TcpLastAck
succ TcpLastAck = TcpListen
succ TcpListen = TcpClosing
succ TcpClosing = TcpNewSynRecv
succ TcpNewSynRecv = TcpMaxStates
succ TcpMaxStates = error "TcpState.succ: TcpMaxStates has no successor"

pred TcpSynSent = TcpEstablished
pred TcpSynRecv = TcpSynSent
pred TcpFinWait1 = TcpSynRecv
pred TcpFinWait2 = TcpFinWait1
pred TcpTimeWait = TcpFinWait2
pred TcpClose = TcpTimeWait
pred TcpCloseWait = TcpClose
pred TcpLastAck = TcpCloseWait
pred TcpListen = TcpLastAck
pred TcpClosing = TcpListen
pred TcpNewSynRecv = TcpClosing
pred TcpMaxStates = TcpNewSynRecv
pred TcpEstablished = error "TcpState.pred: TcpEstablished has no predecessor"

enumFromTo from to = go from
where
end = fromEnum to
go v = case compare (fromEnum v) end of
LT -> v : go (succ v)
EQ -> [v]
GT -> []

enumFrom from = enumFromTo from TcpMaxStates

fromEnum TcpEstablished = 1
fromEnum TcpSynSent = 2
fromEnum TcpSynRecv = 3
fromEnum TcpFinWait1 = 4
fromEnum TcpFinWait2 = 5
fromEnum TcpTimeWait = 6
fromEnum TcpClose = 7
fromEnum TcpCloseWait = 8
fromEnum TcpLastAck = 9
fromEnum TcpListen = 10
fromEnum TcpClosing = 11
fromEnum TcpNewSynRecv = 12
fromEnum TcpMaxStates = 13

toEnum 1 = TcpEstablished
toEnum 2 = TcpSynSent
toEnum 3 = TcpSynRecv
toEnum 4 = TcpFinWait1
toEnum 5 = TcpFinWait2
toEnum 6 = TcpTimeWait
toEnum 7 = TcpClose
toEnum 8 = TcpCloseWait
toEnum 9 = TcpLastAck
toEnum 10 = TcpListen
toEnum 11 = TcpClosing
toEnum 12 = TcpNewSynRecv
toEnum 13 = TcpMaxStates
toEnum unmatched = error ("TcpState.toEnum: Cannot match " ++ show unmatched)
```

I would like to add Data.Bits instance to TcpState so that I can write `TcpEstablished .|. TcpListen`.
I've tried to derive Bits in
`{#enum TCP_ESTABLISHED as TcpState {underscoreToCase} deriving (Eq, Show, Bits)#}`
but it generates:
```
Generated.chs:43:21: error:
• Can't make a derived instance of ‘Bits TcpState’:
‘Bits’ is not a stock derivable class (Eq, Show, etc.)
Try enabling DeriveAnyClass
```
I believe I could hack something together but as it seems like a common usecase. I wondered if there weren't some trick I could use straight from c2hs (could not find it on the wiki).