1. Add 980 drv_usbd.
2. EMAC - move MDC CLK divider before EMAC initialization.
3. Correct NUC980 and M480 CAN RX_MSG_ID_INDEX definition.
4. add USBD cdc demo - vcom_echo.
5. mnt - add mount_table definition.

1. Fix porting driver.
2. Add NAU8822 audio codec driver.
3. Add NUC980 I2S porting driver.

[FIX] fix build problem in drv_crypto.c

fix scheduler bug in simulator.

修正stm32f746-disco和FPU相关的flag错误

[sensor] support TOF sensor class 

bsp/nuclei: Update upload command and document

Although the program elf is uploaded successfully, the upload message is
still "Remote communication error.“, but actually upload works.

After fix, it will be "[Inferior 1 (Remote target) detached]"

By the way, I also checked latest nuclei-sdk 0.3.0 release with latest
rt-thread source code
Signed-off-by: Huaqi Fang <578567190@qq.com>

1. Make up sources and bugfix.
2. Add nu_gpio_pin_get.
3. Add PM operator in USB host driver.
4. Support NUC980 stage 1 and add nk-980iot board.

Merge pull request !86 from 刘泓研/gitee_master

Fix possible array out of bounds

[Bluetrum] add sound and romfs support

[update] stm32mp1 mdk link script file

[timer] Fix the bug that the linked list is still mounted when the si…

[emergency][posix] 实现usleep函数

add dac config for stmf4