archbuild: add architecture-specific mount config
In practice, some architectures may need to mount some files to get a more appropriate chroot.
For example, in the RISC-V port, if we use qemu-user to build, we need to map a correct /proc/cpuinfo, so that software that relies on /proc/cpuinfo to obtain information can be built normally.
Signed-off-by: Celeste Liu CoelacanthusHex@gmail.com
Edited by Celeste Liu