The ptr is set in the following code. So remove the first one.

The digit in octal numbers should with in 0~7. Check on it in
token_proc_number. This issue is found by Clang.

Clang complains about "Null pointer argument in call to string
comparison function". So assert on it.

log_session_lvl is suitable for performance critical places where in
most cases, the log is turned off by level. If the session is const and
the level is greater than session->lvl, the whole function will be
optimized out.

Compiler may do more optimization when the parameter is const.

When MSH enabled, the prompt will change at the two shells. So we should
use dynamic prompt when FINSH_USING_MSH defined.

[USB]fix rt_usbd_set_config() BUG which set the USB device to configuration state before enumerating the device.

Just branch out and no complain on command length == 0;

When DFS_USING_WORKDIR is enabled, msh will try to chdir if the command
is not found. For example, if there is folder named "SD", and there is
no `SD` command and `SD.mo` module, typing "SD" in msh will cd to the
folder.

In more detail, the execution order right now is:

1. built-in command
2. module
3. cd to path

If you have a folder named "ps", you have to run `cd ps` to change the
working dir.

Msh can execute module directly. So try to auto-complete the path when
user press TAB. There is a chance that the path is a module.

2.adjust some viable and micro name
3.some other small fix

This reverts commit 5aeedc4f, reversing
changes made to 3d80e414.

This merge breaks every uart driver in all BSPs. @bright-pan , is there
any way to get this done without breaking existing code?

Add hardware flow support.
Use new struct serial_ringbuffer.