aio: remove _u16 suffix from call. Make return type a uint16_t

Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>

src/maa.i

@@ -289,6 +289,6 @@ typedef struct {
   }
   unsigned int read()
   {
-    return maa_aio_read_u16($self);
+    return maa_aio_read($self);
   }
 }