hw/arm/nseries: Remove invalid/unnecessary n8x0_uart_setup()

hw/arm/nseries: Remove invalid/unnecessary n8x0_uart_setup()

omap2420_mpu_init() introduced in commit 827df9f3c5f ("Add basic
OMAP2 chip support") takes care of creating the 3 UARTs.

Then commit 58a26b477e9 ("Emulate a serial bluetooth HCI with H4+
extensions and attach to n8x0's UART") added n8x0_uart_setup()
which create the UART and connects it to an IRQ output,
overwritting the existing peripheral and its IRQ connection.
This is incorrect.

Fortunately we don't need to fix this, because commit 6da68df7f9b
("hw/arm/nseries: Replace the bluetooth chardev with a "null"
chardev") removed the use of this peripheral. We can simply
remove the code.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20201107193403.436146-4-f4bug@amsat.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>