upm.i: treat upm_result_t like an int in SWIG

Signed-off-by: Jon Trulson <jtrulson@ics.com>

src/upm.i

@@ -5,6 +5,7 @@
 %apply int { speed_t };
 %apply int { mraa_result_t };
 %apply int { mraa::Result };
+%apply int { upm_result_t };
 
 #if (SWIG_JAVASCRIPT_V8)
 %{