Attempt to fix compilation error on windows

Seems simply need to add .exe to msgfmt executable when
adding custom command to SCons.

Don't have windows by hand atm, so can not test for sure.

intern/locale/SConscript

@@ -63,6 +63,10 @@ if env['WITH_BF_INTERNATIONAL']:
 
         locale = env.Clone()
 
+        msgfmt_executable = targetpath
+        if env['OURPLATFORM'] in ('win32-vc', 'win64-vc', 'win32-mingw', 'win64-mingw'):
+            msgfmt_executable += ".exe"
+
         # dependencies
         dependencies = [targetpath]
 
@@ -75,7 +79,7 @@ if env['WITH_BF_INTERNATIONAL']:
             po_file = os.path.join(po_dir, f)
             mo_file = os.path.join(build_dir, os.path.splitext(f)[0] + ".mo")
 
-            command = "\"%s\" \"%s\" \"%s\"" % (targetpath, po_file, mo_file)
+            command = "\"%s\" \"%s\" \"%s\"" % (msgfmt_executable, po_file, mo_file)
 
             locale.Command(mo_file, po_file, command)
             locale.Depends(mo_file, dependencies)