uart.c: fixed typo in debug output

Signed-off-by: Alex Tereschenko <alext.mkrs@gmail.com>
Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>

src/uart/uart.c

@@ -131,7 +131,7 @@ mraa_uart_init(int index)
     }
 
     if (mraa_is_sub_platform_id(index)) {
-        syslog(LOG_NOTICE, "pwm: Using sub platform is not supported");
+        syslog(LOG_NOTICE, "uart: Using sub platform is not supported");
         return NULL;
     }