Fix missing dependency on helper module for helpers added in #1793 (#1811)

PR #1793 introduced helper functions for OS detection in some modules.
These helpers require a module dependency on the 'helper' module.

modules/haskell/init.zsh

@@ -10,6 +10,9 @@ if (( ! $+commands[ghc] )); then
   return 1
 fi
 
+# Load dependencies.
+pmodload 'helper'
+
 # Prepend Cabal per user directories to PATH.
 if is-darwin && [[  -d $HOME/Library/Haskell ]]; then
   path=($HOME/Library/Haskell/bin(/N) $path)

modules/macports/init.zsh

@@ -6,6 +6,9 @@
 #   Sorin Ionescu <sorin.ionescu@gmail.com>
 #
 
+# Load dependencies.
+pmodload 'helper'
+
 # Return if requirements are not found.
 if ! is-darwin; then
   return 1

modules/osx/init.zsh

@@ -5,6 +5,9 @@
 #   Sorin Ionescu <sorin.ionescu@gmail.com>
 #
 
+# Load dependencies.
+pmodload 'helper'
+
 # Return if requirements are not found.
 if ! is-darwin; then
   return 1

modules/perl/init.zsh

@@ -10,6 +10,9 @@ if (( ! $+commands[perl] )); then
   return 1
 fi
 
+# Load dependencies.
+pmodload 'helper'
+
 #
 # Load Perlbrew or plenv
 #

modules/python/init.zsh

@@ -7,6 +7,9 @@
 #   Patrick Bos <egpbos@gmail.com>
 #
 
+# Load dependencies
+pmodload 'helper'
+
 # Load manually installed pyenv into the path
 if [[ -s "${PYENV_ROOT:=$HOME/.pyenv}/bin/pyenv" ]]; then
   path=("${PYENV_ROOT}/bin" $path)

modules/rsync/init.zsh

@@ -10,6 +10,9 @@ if (( ! $+commands[rsync] )); then
   return 1
 fi
 
+# Load dependencies.
+pmodload 'helper'
+
 #
 # Aliases
 #