Use `@since` annotation in GHC.ExecutionStack

While ad532ded fixed the version number, this fixes the markup...

Use `@since` annotation in GHC.ExecutionStack
While ad532ded fixed the version number, this fixes the markup...
2ef35d8f · Herbert Valerio Riedel · aadde2b9 · 2ef35d8f · 2ef35d8f
Commit 2ef35d8f authored Apr 11, 2016 by Herbert Valerio Riedel 🕺
--- a/libraries/base/GHC/ExecutionStack.hs
+++ b/libraries/base/GHC/ExecutionStack.hs
@@ -26,7 +26,7 @@
 --  ,("RTS expects libdw","YES")
 -- @
 --
-- /Since: 4.9.0.0/
+-- @since 4.9.0.0
 -----------------------------------------------------------------------------

 module GHC.ExecutionStack (

--- a/libraries/base/GHC/ExecutionStack/Internal.hsc
+++ b/libraries/base/GHC/ExecutionStack/Internal.hsc
@@ -10,7 +10,7 @@
 --
 -- Internals of the `GHC.ExecutionStack` module
 --
-- /Since: 4.9.0.0/
+-- @since 4.9.0.0
 -----------------------------------------------------------------------------

 #include "HsFFI.h"