ARM: dts: aspeed: everest: Add IBM Operation Panel I2C device

ARM: dts: aspeed: everest: Add IBM Operation Panel I2C device

Set I2C bus 14 to multi-master mode and add the panel device that will
register the I2C controller as a slave device.
In addition, in early Everest systems, the panel device was behind an
I2C switch, which doesn't work for slave mode. Get it working (albeit
unreliably, since a master transaction might switch the switch at any
moment) by defaulting the switch channel to the one with the panel.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20211020215321.33960-5-eajames@linux.ibm.com
Signed-off-by: Joel Stanley <joel@jms.id.au>