synchronize virtual memory system works.
adding kernel virtual memory management layer for page-based MMU enabled architecture
porting libcpu MMU codes
porting lwp memory related codes

增加静态object 名字，用户可以根据内存实际使用情况决定使用动态还是静态。适用于资源极度受限的情况下使用。该功能在RT-Thread完整版本中不常用，主要用于RT-Thread Nano，以缩减对内存的占用。由于没有动态拼接支持，在静态名字下，空闲线程的名字在多核时将命名成相同的名字。

* [dfs] sync cromfs

* [rt-smart]Weaken RT_USING_LWP, use RT_USING_SMART as macro configuration

* [format] fix some format issue.

* [rtdef] rename RT_WEAK attribute as rt_weak

* [rtdef] rename RT_USED attribute as rt_used

* [rtdef] rename RT_SECTION attribute as rt_section

* [rtdef] rename ALIGN attribute as rt_align

* [legacy] add RT_USED ALIGN RT_SECTION RT_WEAK as legacy support

* [risc-v/libcpu] porting Smart & RTOS
* [fix] rv64 plic
* [risc-v/rv64] remove macro in rtdef

* Synchronize the code of the rt mart branch to the master branch.
  * TTY device
  * Add lwP code from rt-smart
  * Add vnode in DFS, but DFS will be re-write for rt-smart
  * There are three libcpu for rt-smart:
    * arm/cortex-a, arm/aarch64
    * riscv64
Co-authored-by: NRbb666 <zhangbingru@rt-thread.com>
Co-authored-by: Nzhkag <zhkag@foxmail.com>

目前基本功能已经可以在QEMU上跑起来，但是pthread和内核signal选中会报冲突。先合并一版本，后续解决这些问题。

[bsp][c28x] add support to not disable global interrupt in context-switch to enable zero-latency isr for critical interrupts.

版本控制规范：https://semver.org/

目前的版本子号不是很规范，其中RT_VERSION甚至和VS那边造成了冲突
```c
/* RT-Thread version information */
#define RT_VERSION                      4L              /**< major version number */
#define RT_SUBVERSION                   1L              /**< minor version number */
#define RT_REVISION                     1L              /**< revise version number */
```

参考ESP32：
```c
/** Major version number (X.x.x) */
#define ESP_ARDUINO_VERSION_MAJOR   2
/** Minor version number (x.X.x) */
#define ESP_ARDUINO_VERSION_MINOR   0
/** Patch version number (x.x.X) */
#define ESP_ARDUINO_VERSION_PATCH   3
```

建议改成：
```c
/* Major version number (X.x.x) */
#define RT_VERSION_MAJOR   4
/* Minor version number (x.X.x) */
#define RT_VERSION_MINOR   2
/* Patch version number (x.x.X) */
#define RT_VERSION_PATCH   0
```

解决 tms320f28379d bsp 启动的问题。主要改动如下。

修正context.s中汇编代码错误。在旧版的代码中，操作数为32位而汇编命令却使用了针对16位数据的命令MOV，导致程序在某些情况无法正常启动线程。
由于C28x的平台下，SP只支持16bit寻址，所以用于线程空间存放的heap以及ebss段都需要放在低16位的空间，针对这个问题修改了CMD文件。此外还增加基于CMD文件基于RAM的支持，方便调试。
新增rtdef.h中RT_SECTION，RT_USED，ALIGN和RT_WEAK的定义。旧版bsp中这些定义为空，导致INIT_EXPORT注册的函数失效。
修改程序启动代码，在程序入口直接调用原生启动代码
以上改动在LAUNCHXL-F28379D 通过了测试。

* [fix] the risk for function exit() when open pthread support.
* [update] modify annotation from "user data" to "pthread_data".

This reverts commit 6a05ddf6.

* [add] the function realization of signal for posix.
* [update] the posix support for armclang.
* [add] the new macro "RT_USING_POSIX_TIMER".
* [modify] select "RT_USING_SOFT_TIMER" when use posix'timer.
* [bug] optimize the logic for the "time_xxx" functions.
* [modify] use "RT_USING_POSIX_TIMER" to protect the macro definition.
* [modify] error code when except happened.
* [delete] the "environ" is useless at this time.

- Backward compatible with existing function-pointer based hooking method
- Using RT_USING_HOOK as an on/off switch
- Introducing a new low-overhead macro-based hooking method

1. Add RTGRAPHIC_CTRL_PAN_DISPLAY and RTGRAPHIC_CTRL_WAIT_VSYNC control command.
2. Add calibration data of 480x272 ADC touching.
3. Add 480x272 LCD panel menu option and driver.
4. Update lv_conf.h.