v1.2.1 to support STM32 + LAN8720

### Releases v1.2.1

1. Add support to many **STM32F4 and STM32F7 (without TLS/SSL)** using `LAN8720` Ethernet, such as F407xx, NUCLEO_F429ZI, DISCO_F746NG, NUCLEO_F746ZG, NUCLEO_F756ZG, etc.
2. Add examples for `STM32_LAN8720`

Author: khoih-prog

README.md

@@ -329,12 +329,13 @@ Connect as follows. To program, use **STM32CubeProgrammer** or Arduino IDE with
 |:-:|:-:|:-:|
 |BOOT0|<--->|3.3V|
 
-- Jumper settings twhen running normally to avoid accidentally reprogram
+- Jumper settings when running normally to avoid accidentally reprogram
 
 |From|<--->|To|
 |:-:|:-:|:-:|
 |BOOT0|<--->|GND|
 
+---
 
 |STLink|<--->|STM32F4|
 |:-:|:-:|:-:|