serial: Make SERIAL_MVEBU_UART depend on ARCH_MVEBU

Enabling support for the UART on Marvell EBU SoCs only make sense when
compiling for Marvell EBU SoCs, unless compile-testing.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/Kconfig

@@ -1605,6 +1605,7 @@ config SERIAL_STM32_CONSOLE
 
 config SERIAL_MVEBU_UART
 	bool "Marvell EBU serial port support"
+	depends on ARCH_MVEBU || COMPILE_TEST
 	select SERIAL_CORE
 	help
 	  This driver is for Marvell EBU SoC's UART. If you have a machine