Use 'unless' instead of 'if not'

Author: mwulftange

modules/auxiliary/admin/http/synology_dsm_sliceupload_exec_noauth.rb

@@ -123,7 +123,7 @@ def run
       'data'    => post_body
     })
 
-    if !res or res.code != 200 or !res.body.include?('error_noprivilege')
+    unless res and res.code == 200 and res.body.include?('error_noprivilege')
       print_error("#{peer} - Unexpected response, probably the exploit failed")
       return
     end
@@ -134,7 +134,7 @@ def run
       'uri'    => '/redirect.cgi'
     })
 
-    if !res or res.code != 200
+    unless res and res.code == 200
       print_error("#{peer} - Unexpected response, probably the exploit failed")
       return
     end