Fix rapid7#3975 - Register TARGETURI, not URI

The module should register TARGETURI and call #target_uri for
URI validation.

Author: wchen-r7

modules/auxiliary/scanner/http/tomcat_mgr_login.rb

@@ -58,7 +58,7 @@ def initialize
     register_options(
       [
         Opt::RPORT(8080),
-        OptString.new('URI', [true, "URI for Manager login. Default is /manager/html", "/manager/html"]),
+        OptString.new('TARGETURI', [true, "URI for Manager login. Default is /manager/html", "/manager/html"]),
         OptPath.new('USERPASS_FILE',  [ false, "File containing users and passwords separated by space, one pair per line",
           File.join(Msf::Config.data_directory, "wordlists", "tomcat_mgr_default_userpass.txt") ]),
         OptPath.new('USER_FILE',  [ false, "File containing users, one per line",
@@ -72,7 +72,7 @@ def initialize
 
   def run_host(ip)
     begin
-      uri = normalize_uri(datastore['URI'])
+      uri = normalize_uri(target_uri.path)
       res = send_request_cgi({
         'uri'     => uri,
         'method'  => 'GET',