fix usb util error, bump version to v4.11.4

Author: Neutree

examples/tools/maixcam_switch_usb_mode.py

@@ -1,6 +1,6 @@
 import os
 
-cmd_restart = "/etc/init.d/S03usbdev stop &&/etc/init.d/S03usbdev start"
+cmd_restart = "/usr/bin/usb_util stop && /usr/bin/usb_util start"
 
 def usb_devive(device_list):
     if os.path.exists("/boot/usb.host"):

maix/version.py

@@ -3,6 +3,6 @@
 
 version_major = 4
 version_minor = 11
-version_patch = 3
+version_patch = 4
 
 __version__ = "{}.{}.{}".format(version_major, version_minor, version_patch)