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

更新的SDK2.12.1更新imxrt1060的驱动

* [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

1、修复ksz8081.c编译错误；
2、修复rt1170网络驱动问题

* 增加千兆网络配置

* 适配最新1170SDK2.12版本

* 增加MAC层驱动配置

* add rt1170 bsp
* add rt1020 bsp

2. 恢复了1052的BSP的初始配置

2. 在IMXRT的Libraries中增加了peripherals目录，用于具体型号的设备驱动相关的代码的实现，不应与MCU的平台相关，实现PHY的设备对象中的相关接口。
3. 修改了BSP中的Sconstruct文件，增加了peripherals目录的构建
4. 修改了KEIL环境的SCT文件，用于实现以太网功能

1. Add "drv_eth.c" for all imxrt platforms.
2. Add ksz8081 phy driver for imxrt1052-nxp-evk board.
3. Disable the LED demo in main.c file if enable the ENET
   and ksz8081 phy, because the PINs of LED and ksz8081
   reset are from the same GPIO.
4. Update the relevant Kconfig and Sconscript files.
Signed-off-by: NGavin Liu <gavin-liugang@outlook.com>