Patch unix-compat-0.6 to build with unix-2.8.*

Code adapted from https://github.com/jacobstanley/unix-compat/pull/60

patches/unix-compat-0.6.patch

+diff --git a/src/System/PosixCompat/User.hsc b/src/System/PosixCompat/User.hsc
+index b5b07e2..f4c86c4 100644
+--- a/src/System/PosixCompat/User.hsc
++++ b/src/System/PosixCompat/User.hsc
+@@ -3,7 +3,10 @@
+ {-|
+ This module makes the operations exported by @System.Posix.User@
+ available on all platforms. On POSIX systems it re-exports operations from
+-@System.Posix.User@. On other platforms it provides dummy implementations.
++@System.Posix.User@. And if using this module with unix package since version
++@2.8@ on POSIX systems, it redefines some data type and functions for
++compatibilities with unix package prior to version @2.8@. On other platforms it
++provides dummy implementations.
+ -}
+ module System.PosixCompat.User (
+     -- * User environment
+@@ -37,7 +40,78 @@ module System.PosixCompat.User (
+ 
+ #include "HsUnixCompat.h"
+ 
++#if MIN_VERSION_unix(2, 8, 0)
++import System.Posix.Types (GroupID, UserID)
+ import System.Posix.User
++    ( getRealUserID
++    , getRealGroupID
++    , getEffectiveUserID
++    , getEffectiveGroupID
++    , getGroups
++    , getLoginName
++    , getEffectiveUserName
++    , setUserID
++    , setGroupID
++    )
++import qualified System.Posix.User as User
++import qualified System.Posix.User.ByteString as BUser
++
++data GroupEntry = GroupEntry
++    { groupName     :: String
++    , groupPassword :: String
++    , groupID       :: GroupID
++    , groupMembers  :: [String]
++    } deriving (Show, Read, Eq)
++
++toCompatGroupEntry :: BUser.GroupEntry -> GroupEntry
++toCompatGroupEntry entry = GroupEntry
++    { groupName = User.groupName entry
++    , groupPassword = User.groupPassword entry
++    , groupID = User.groupID entry
++    , groupMembers = User.groupMembers entry
++    }
++
++getGroupEntryForID :: GroupID -> IO GroupEntry
++getGroupEntryForID = fmap toCompatGroupEntry . User.getGroupEntryForID
++
++getGroupEntryForName :: String -> IO GroupEntry
++getGroupEntryForName = fmap toCompatGroupEntry . User.getGroupEntryForName
++
++getAllGroupEntries :: IO [GroupEntry]
++getAllGroupEntries = fmap (map toCompatGroupEntry) User.getAllGroupEntries
++
++data UserEntry = UserEntry
++    { userName      :: String
++    , userPassword  :: String
++    , userID        :: UserID
++    , userGroupID   :: GroupID
++    , userGecos     :: String
++    , homeDirectory :: String
++    , userShell     :: String
++    } deriving (Show, Read, Eq)
++
++toCompatUserEntry :: BUser.UserEntry -> UserEntry
++toCompatUserEntry entry = UserEntry
++    { userName = User.userName entry
++    , userPassword = User.userPassword entry
++    , userID = User.userID entry
++    , userGroupID = User.userGroupID entry
++    , userGecos = User.userGecos entry
++    , homeDirectory = User.homeDirectory entry
++    , userShell = User.userShell entry
++    }
++
++getUserEntryForID :: UserID -> IO UserEntry
++getUserEntryForID = fmap toCompatUserEntry . User.getUserEntryForID
++
++getUserEntryForName :: String -> IO UserEntry
++getUserEntryForName = fmap toCompatUserEntry . User.getUserEntryForName
++
++getAllUserEntries :: IO [UserEntry]
++getAllUserEntries = fmap (map toCompatUserEntry) User.getAllUserEntries
++#else
++import System.Posix.User
++#endif
+ 
+ #if __GLASGOW_HASKELL__<605
+ getAllGroupEntries :: IO [GroupEntry]