Hi Fred,

Add ACPI support for serial attached devices.

Currently, serial devices are not set as enumerated during ACPI scan for SPI
or i2c buses (but not for UART). This should also be done for UART serial
devices.
I renamed *spi_i2c_slave* to *serial_bus_slave* to reflect this.

For hci_bcm, this needs Hans de Goede's "Bluetooth: hci_bcm: Add (runtime)pm
support to the serdev drv" patches to work.

Tested on T100TA with Broadcom BCM2E39.

Since RFC:
 - Add or reword commit messages
 - Rename *serial_slave* to *serial_bus_slave*
 - Add specific check for Apple in acpi_is_serial_bus_slave(), thanks to
   Lukas Wunner
 - Update comment in acpi_default_enumeration()
 - Remove patch 3 "Bluetooth: hci_bcm: Add ACPI serdev support for BCM2E39"
   in favor of patches from Hans de Goede

I already applied Hans’ patch series to bluetooth-next tree. And I have no objections or comments for these changes. They should be reviewed and acked by the appropriate maintainers as well, but from my side this looks good.

Acked-by: Marcel Holtmann <marcel@holtmann.org>

What we should discuss on how we get them upstream since besides the Bluetooth subsystem, they cover ACPI and TTY subsystems.

Regards

Marcel