Add thead to linux-next

[Drew Fustini]

Hi Stephen,

I've taken over the maintainer role for for T-Head SoCs [1] and I've
set up a tree that I will being using to send pull requests to Arnd.

Please add these branches to linux-next:

thead-dt-fixes git https://github.com/pdp7/linux.git#thead-dt-fixes
thead-dt-for-next git https://github.com/pdp7/linux.git#thead-dt-for-next

Thanks,
Drew

[1] https://lore.kernel.org/linux-riscv/20240620162522.386-1-jszhang@xxxxxxxxxx/