AutoChips/AC781x: Add svd file from official pack archive

[VincentDary]

Add AutoChips AC781x from official vendor.

Pack file direct link: https://autochips.com/uploads/file/20240415/2024041512322026.zip

Developer Resources: https://autochips.com/developersr.html?ty=74&tty=81

AC781x Reference Manual: https://autochips.com/uploads/file/20230515/2023051516524130.pdf

To check the SVD file authenticity, follow these instructions:

$ wget https://autochips.com/uploads/file/20240415/2024041512322026.zip
$ unzip 2024041512322026.zip
$ unzip AutoChips.AC781x_DFP.1.1.4.pack -d AutoChips.AC781x_DFP.1.1.4
$ cd AutoChips.AC781x_DFP.1.1.4/SVD
$ sha512sum AC781x.svd > ../../AutoChips_AC781x_svd_sha512.txt
$ cd ../..
$ git clone https://github.com/VincentDary/cmsis-svd-data.git
$ cd cmsis-svd-data
$ git checkout autochips-AC781x-SVD
$ cd data/AutoChips
$ sha512sum -c ../../../AutoChips_AC781x_svd_sha512.txt
AC781x.svd: OK
$ echo $?
0

AutoChips_AC781x_svd_sha512.txt