palmetto: Update I2C hwmon paths for the 5.0 kernel

In the 5.0 Linux kernel, an I2C device path segment changed:
    i2c@1e78a000 -> bus@1e78a000

Change-Id: Icb9788bc6de9861000095fc6c7f16f456984f6c6
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
4 files changed