[commit: ghc] : Bump mtl submodule to 2.2.2 (b183d44)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : 
Link       : http://ghc.haskell.org/trac/ghc/changeset/b183d44a1ff5a6caf22db1bf5f7de23a3e58a6f0/ghc

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commit b183d44a1ff5a6caf22db1bf5f7de23a3e58a6f0
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Mon Apr 16 09:49:58 2018 -0400

    Bump mtl submodule to 2.2.2


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b183d44a1ff5a6caf22db1bf5f7de23a3e58a6f0
 libraries/mtl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/mtl b/libraries/mtl
index bf4af11..c7d3967 160000
--- a/libraries/mtl
+++ b/libraries/mtl
@@ -1 +1 @@
-Subproject commit bf4af114ba3d35b2937fc74926aa49e128dd6c1f
+Subproject commit c7d396732bd45e409478bd4df1d0ca95d6f39356