tty: serial: 8250: Relocate macros within 8250_pci.c

Move PCI_DEVICE_ID macros to the top so that these macros can be used
throughout 8250_pci.c

Signed-off-by: Crescent CY Hsieh <crescentcy.hsieh@moxa.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20231018091739.10125-4-crescentcy.hsieh@moxa.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>