* [rt-smart/mem] remove pv_offset

* [rt-smart] list kernel space command

* [rt-smart] restore ioremap region

* [revert] restore kernel space isolation

* [rt-smart/pv_off] code format

* [rt-smart] add get_pvoff()

* [pvoffset] pvoff as constant for C codes

* [pvoff] pvoff as interfaces

* [FDT] Fix POSIX compatibility for string.h

* [FDT] format libfdt code.

* [FDT] format libfdt code.

这个函数实现了原先的挂载功能，并且调用pin框架，初始化cs引脚，是一个功能相对完善的挂载函数。用户也能更简单的使用。
该函数取代rt_spi_bus_attach_device，后续rt_spi_bus_attach_device会被逐渐淘汰掉。新的BSP以及软件包应当使用rt_spi_bus_attach_device_cspin新函数。

STM32L475潘多拉测试通过。

* ringbuffer size boost to 32bit
* 添加ringbuffer测试demo
related: #682
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Co-authored-by: Zxy <1308465141@qq.com>
Co-authored-by: Man, Jianting (Meco) <920369182@qq.com>

rt_ssize_t can give negative error code, which follows the unix style correctly

🐞 fix(components/dfs/filesystems/tmpfs/dfs_tmpfs.c): cannot open the same file repeatedly in 'w' mode

更新的SDK2.12.1更新imxrt1060的驱动

* Add ADT Kconfig and fix MMU kconfig issue in Cortex-A

* [BSP] enable ADT

命令交互应使用rt_kprintf，而非LOG_x

* [bsp_lpc55sxx] i2c,rtc bsp update

1. add i2c DMA mode
2. enable rtc driver

* [bsp_lpc55sxx] formmat code

using formmating.py for format code

* [lpc55sxx] remove .gitignore

* [bsp][lpc55sxx] update bsp driver

1. update sdif driver, enable DFS, FAT32
2. update rtc driver