[commit: ghc] master: Bump unix submodule (b6a2691)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/b6a2691aeb55e990080130d996f63bb40595885e/ghc

>---------------------------------------------------------------

commit b6a2691aeb55e990080130d996f63bb40595885e
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Wed Nov 29 15:23:41 2017 -0500

    Bump unix submodule
    
    Fixes FreeBSD build.


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b6a2691aeb55e990080130d996f63bb40595885e
 libraries/unix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/unix b/libraries/unix
index 748e8b4..41c5776 160000
--- a/libraries/unix
+++ b/libraries/unix
@@ -1 +1 @@
-Subproject commit 748e8b41e06eeab8b9086bf481ebca5218639f5c
+Subproject commit 41c5776162b60e0739a7559ceab03b9c3a444516