修正关机操作，关机操作应该是‘echo o >/proc/sysrq-trigger’，

而不是‘echo b >/proc/sysrq-trigger’

	修改：      interface/ri_install.py

Signed-off-by: PengZhihui <zhihuipeng@linx-info.com>

interface/ri_install.py

@@ -42,7 +42,7 @@ def install_over(ret):
             print "shutdown ..."
             os.system("sync")
             os.system("eject")
-            os.system("echo b >/proc/sysrq-trigger")
+            os.system("echo o >/proc/sysrq-trigger")
         elif ret_set_task_over == 'nothing':
             display.root_destroy()