Fix from Alfred Perlstein

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%40966

src/joystick/bsd/SDL_sysjoystick.c

@@ -160,6 +160,7 @@ SDL_SYS_JoystickInit(void)
 			SDL_numjoysticks++;
 		} else {
 			free(joynames[nj.index]);
+			joynames[nj.index] = NULL;
 		}
 	}
 	for (i = 0; i < MAX_JOY_JOYS; i++) {