doc: remove GHC hook documentation and update redirects

doc/hooks/ghc.section.md

@@ -1,3 +0,0 @@
-# GHC {#ghc}
-
-Creates a temporary package database and registers every Haskell build input in it (TODO: how?).

doc/hooks/index.md

@@ -17,7 +17,6 @@ check-phase-thread-limit-hook.section.md
 cmake.section.md
 desktop-file-utils.section.md
 gdk-pixbuf.section.md
-ghc.section.md
 gnome.section.md
 haredo.section.md
 installShellFiles.section.md

doc/redirects.json

@@ -2783,9 +2783,6 @@
   "glycin-dont-wrap": [
     "index.html#glycin-dont-wrap"
   ],
-  "ghc": [
-    "index.html#ghc"
-  ],
   "gnome-platform": [
     "index.html#gnome-platform"
   ],
@@ -3633,7 +3630,8 @@
     "index.html#hareHook-cross-compilation"
   ],
   "haskell": [
-    "index.html#haskell"
+    "index.html#haskell",
+    "index.html#ghc"
   ],
   "haskell-available-packages": [
     "index.html#haskell-available-packages"