serial: 8250: Fix add preferred console for serial8250_isa_init_ports()

serial: 8250: Fix add preferred console for serial8250_isa_init_ports()

We need to inline serial_base_add_isa_preferred_console()  based on
CONFIG_SERIAL_8250_CONSOLE and not based on CONFIG_SERIAL_CORE_CONSOLE.
Otherwise we can get the follwoing error as noted by Stephen:

ERROR: modpost: "serial_base_add_isa_preferred_console"
[drivers/tty/serial/8250/8250.ko] undefined!

We also have a duplicate inlined serial_base_add_isa_preferred_console(),
in serial_base_bus.c added by the same commit by accident, let's drop it.

Fixes: a8b04cfe7dad ("serial: 8250: Add preferred console in serial8250_isa_init_ports()")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20240411080622.11929-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>