Move to buildroot version 2024.11 with gcc 14.x

Delete old buildroot config 2024.08.config, and replace it with
the new file 2024.11.config which is generated by buildroot version
2024.11.

Also, disable BR2_TOOLCHAIN_EXTERNAL_GCC_13 and enable
BR2_TOOLCHAIN_EXTERNAL_GCC_14 to move to new gcc version.

Signed-off-by: Jagdish Gediya <jagdish.gediya@arm.com>