serial: 8250: Correct Kconfig help text for blacklisted PCI devices

Correct the Kconfig help text for SERIAL_8250_LPSS, SERIAL_8250_MID and
SERIAL_8250_PERICOM configuration options for dedicated PCI UART drivers
that have been blacklisted in the generic PCI 8250 UART driver and as
from commit a13e19cf ("serial: 8250_lpss: split LPSS driver to
separate module"), commit d9eda9ba ("serial: 8250_pci: Intel MID
UART support to its own driver"), and commit fcfd3c09 ("serial:
8250_pci: Split out Pericom driver") respectively are not handled by
said driver anymore (rather than for extra features only, as the current
text indicates), and therefore require the respective dedicated drivers
to work at all.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2202121704560.34636@angie.orcam.me.uk


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>