hw/char/ibex_uart: Make the register layout private

We don't need to expose the register layout in the public header, so
don't.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Message-id: c437f570b2b30ab4170387a3ba2fad7d116a4986.1624001156.git.alistair.francis@wdc.com
2 files changed