No special Sexps for options/buffer calls in HAML

Brakeman was generating invalid call Sexps with `:_hamlout`
as the target for `_hamlout.options` and `hamlout.buffer`.
However, these special Sexps were not really be handled in Brakeman
anywhere, and there was no real reason to make special Sexps for them.

lib/brakeman/processors/haml_template_processor.rb

@@ -29,14 +29,12 @@ class Brakeman::HamlTemplateProcessor < Brakeman::TemplateProcessor
 
     method = exp.method
 
-    if (call? target and target.method == :_hamlout) or target == :_hamlout
+    if (call? target and target.method == :_hamlout)
       res = case method
             when :adjust_tabs, :rstrip!, :attributes #Check attributes, maybe?
               ignore
-            when :options
-              Sexp.new :call, :_hamlout, :options, exp.arglist
-            when :buffer
-              Sexp.new :call, :_hamlout, :buffer, exp.arglist
+            when :options, :buffer
+              exp
             when :open_tag
               Sexp.new(:tag, process(exp.arglist))
             else