serial: make SiFive serial drivers depend on ARCH_ symbols

As part of converting RISC-V SOC_FOO symbols to ARCH_FOO to match the
use of such symbols on other architectures, convert the SiFive serial
driver Kconfig entries from the SOC_ symbols to ARCH_ instead.
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230406-carnival-aspirate-fcf69a30078c@spudSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/Kconfig

@@ -951,7 +951,7 @@ config SERIAL_OMAP_CONSOLE
 config SERIAL_SIFIVE
 	tristate "SiFive UART support"
 	depends on OF
-	default SOC_SIFIVE || SOC_CANAAN
+	default ARCH_SIFIVE || ARCH_CANAAN
 	select SERIAL_CORE
 	help
 	  Select this option if you are building a kernel for a device that
@@ -961,7 +961,7 @@ config SERIAL_SIFIVE
 config SERIAL_SIFIVE_CONSOLE
 	bool "Console on SiFive UART"
 	depends on SERIAL_SIFIVE=y
-	default SOC_SIFIVE || SOC_CANAAN
+	default ARCH_SIFIVE || ARCH_CANAAN
 	select SERIAL_CORE_CONSOLE
 	select SERIAL_EARLYCON
 	help