Update table of contents

Author: Disasm

README.md

@@ -19,6 +19,7 @@ This project is developed and maintained by the [Resources team][team].
     * [Real-time Operating System](#real-time-operating-system-rtos)
     * [Real-time tools](#real-time-tools)
 * [Peripheral Access Crates](#peripheral-access-crates)
+    * [GigaDevice](#gigadevice)
     * [Microchip](#microchip)
     * [Nordic](#nordic)
     * [NXP](#nxp)
@@ -31,6 +32,7 @@ This project is developed and maintained by the [Resources team][team].
     * [XMC](#xmc)
 * [HAL implementation crates](#hal-implementation-crates)
     * [OS](#os)
+    * [GigaDevice](#gigadevice-1)
     * [Nordic](#nordic-1)
     * [NXP](#nxp-1)
     * [SiFive](#sifive-1)
@@ -46,7 +48,9 @@ This project is developed and maintained by the [Resources team][team].
 * [Board support crates](#board-support-crates)
     * [Nordic](#nordic-2)
     * [NXP](#nxp-2)
+    * [SeeedStudio](#seeedstudio)
     * [SiFive](#sifive-2)
+    * [Sipeed](#sipeed)
     * [Sony](#sony)
     * [STMicroelectronics](#stmicroelectronics-2)
     * [Texas Instruments](#texas-instruments-2)