Added stub for RasHangUpA().

diff --git a/dlls/rasapi32/rasapi.c b/dlls/rasapi32/rasapi.c
index 7a8a5bc..a1f9f90 100644
--- a/dlls/rasapi32/rasapi.c
+++ b/dlls/rasapi32/rasapi.c
@@ -43,3 +43,12 @@
             lpRasDialParams,lpfPassword);
 	return 0;
 }
+
+/**************************************************************************
+ *                 RasHangUpA			[RASAPI32.556]
+ */
+DWORD WINAPI RasHangUpA( HRASCONN hrasconn)
+{
+	FIXME("(%x),stub!\n",hrasconn);
+	return 0;
+}