boards: gd32: Update outdated links

This commit updates the outdated links for the GD32 boards.

Signed-off-by: Stephanos Ioannidis <[email protected]>

Author: stephanosio

boards/arm/gd32f403z_eval/doc/index.rst

@@ -207,10 +207,10 @@ is :code:`$HOME/.local/bin`.
 	https://www.gigadevice.com/products/microcontrollers/gd32/arm-cortex-m4/high-performance-line/gd32f403-series/
 
 .. _GD32F403 Datasheet:
-	http://www.gd32mcu.com/data/documents/shujushouce/GD32F403xx_Datasheet_Rev1.3.pdf
+	https://gd32mcu.com/data/documents/datasheet/GD32F403xx_Datasheet_Rev1.3.pdf
 
 .. _GD32F403 Reference Manual:
-	http://www.gd32mcu.com/data/documents/yingyongbiji/GD32F403_User_Manual_Rev2.4.pdf
+	https://gd32mcu.com/data/documents/userManual/GD32F403_User_Manual_Rev2.6.pdf
 
 .. _GD32F403Z Eval Schematics:
 	http://www.gd32mcu.com/download/down/document_id/270/path_type/1

boards/arm/gd32f470i_eval/doc/index.rst

@@ -160,7 +160,7 @@ allows flash programming and debugging over USB. There is also a JTAG header
    https://www.gigadevice.com/microcontroller/gd32f470ikh6/
 
 .. _GD32F470xx Datasheet:
-   https://gd32mcu.21ic.com/data/documents/shujushouce/GD32F470xx_Datasheet_Rev1.1.pdf
+   https://gd32mcu.com/data/documents/datasheet/GD32F470xx_Datasheet_Rev1.3.pdf
 
 .. _GD32F4xx User Manual:
-   https://www.gd32mcu.com/data/documents/yingyongbiji/GD32F4xx_User_Manual_Rev2.6.pdf
+   https://gd32mcu.com/data/documents/userManual/GD32F4xx_User_Manual_Rev2.7.pdf

boards/riscv/gd32vf103v_eval/doc/index.rst

@@ -150,7 +150,7 @@ allows flash programming and debugging over USB. There is also a JTAG header
    https://www.gigadevice.com/datasheet/gd32vf103xxxx-datasheet/
 
 .. _GD32VF103 User Manual:
-   https://gd32mcu.21ic.com/data/documents/shujushouce/GD32VF103_User_Manual_EN_V1.2.pdf
+   https://www.gd32mcu.com/data/documents/userManual/GD32VF103_User_Manual_Rev1.4.pdf
 
 .. _GD32VF103V-EVAL Documents:
    https://github.com/riscv-mcu/GD32VF103_Demo_Suites/tree/master/GD32VF103V_EVAL_Demo_Suites/Docs

boards/riscv/longan_nano/doc/index.rst

@@ -16,7 +16,7 @@ More information can be found on:
 
 - `Sipeed Longan website <https://longan.sipeed.com/en/>`_
 - `GD32VF103 datasheet <https://www.gigadevice.com/datasheet/gd32vf103xxxx-datasheet/>`_
-- `GD32VF103 user manual <http://www.gd32mcu.com/data/documents/shujushouce/GD32VF103_User_Manual_EN_V1.2.pdf>`_
+- `GD32VF103 user manual <https://www.gd32mcu.com/data/documents/userManual/GD32VF103_User_Manual_Rev1.4.pdf>`_
 - `Nuclei website <https://www.nucleisys.com/download.php>`_
 - `Nuclei Bumblebee core documents <https://github.com/nucleisys/Bumblebee_Core_Doc>`_
 - `Nuclei ISA Spec <https://doc.nucleisys.com/nuclei_spec/>`_