Drop "ifdef GHC"s on INLINABLE pragmas (#1167)

These were added long ago in 06e91ac as an improvement on GHC over the
already existing INLINE pragmas. We can get rid of these unnecessary
(and confusing to contributors) ifdefs today since we do not have other
compilers where we want the non-INLINABLE behavior to apply.

While INLINABLE is not a standard pragma listed in the Haskell 2010
report, the report also specifies that unrecognized pragmas should be
ignored. So we don't expect this to cause issues for non-GHC compilers.
MicroHs quietly ignores them as expected.

Author: meooow25

containers/src/Data/IntMap/Internal.hs

@@ -3391,11 +3391,7 @@ fromSetA f (IntSet.Tip kx bm) = buildTree f kx bm (IntSet.suffixBitMask + 1)
                 (Bin (Prefix (prefix .|. bits2)))
                   (buildTree g prefix bmask bits2)
                   (buildTree g (prefix + bits2) (bmask `shiftRL` bits2) bits2)
-#if __GLASGOW_HASKELL__
 {-# INLINABLE fromSetA #-}
-#else
-{-# INLINE fromSetA #-}
-#endif
 
 {--------------------------------------------------------------------
   Lists

containers/src/Data/IntMap/Strict/Internal.hs

@@ -1116,11 +1116,7 @@ fromSetA f (IntSet.Tip kx bm) = buildTree f kx bm (IntSet.suffixBitMask + 1)
                 (Bin (Prefix (prefix .|. bits2)))
                   (buildTree g prefix bmask bits2)
                   (buildTree g (prefix + bits2) (bmask `shiftRL` bits2) bits2)
-#if __GLASGOW_HASKELL__
 {-# INLINABLE fromSetA #-}
-#else
-{-# INLINE fromSetA #-}
-#endif
 
 {--------------------------------------------------------------------
   Lists

containers/src/Data/IntSet/Internal.hs

@@ -618,9 +618,7 @@ alterF f k s = fmap choose (f member_)
 
     choose True  = inserted
     choose False = deleted
-#ifndef __GLASGOW_HASKELL__
-{-# INLINE alterF #-}
-#else
+#ifdef __GLASGOW_HASKELL__
 {-# INLINABLE [2] alterF #-}
 
 {-# RULES