v1.25.0

This is a major Buildroot, toolchain, and Linux kernel update that also adds
support for using Scenic without customizing the system.

Please see nerves_system_br v1.25.0 release notes
for upgrade instructions if you've forked this system.

• New features

  • Add libcairo for Scenic support

• Updated dependencies

  • Linux 6.1.63 (Raspberry Pi stable_20231123 release)
  • nerves_system_br v1.25.2
  • Buildroot 2023.08.4
  • Erlang/OTP 26.1.2