Merge branch 'mlxsw-i2c'

Jiri Pirko says:

====================
mlxsw: Introduce support for I2C bus

Vadim says:

This patchset adds I2C access support for SwitchX, SwitchX2, SwitchIB,
SwitchIB2 and Spectrum silicones.

It contains:
 - Small changes in mlxsw core code, needed for I2C bus support;
 - I2C driver, which obtains I2C input/output mailboxes setting and
   provides command interface implementation.
 - Minimal driver, which works on top of I2C driver and allows running
   of mlxsw command interface over I2C bus;

Use case:
On system, which does not have PCI to ASIC (BMC), hwmon functionality
(sensors, pwm, tacho) will be available through I2C.

Usage (manual probing):
echo mlxsw_minimal 0x48 > /sys/bus/i2c/devices/i2c-2/new_device

Sysfs interface:
/sys/bus/i2c/devices/2-0048/hwmon/hwmon5/pwm1
/sys/bus/i2c/devices/2-0048/hwmon/hwmon5/temp1_input
====================

Signed-off-by: David S. Miller <davem@davemloft.net>