CHROMIUM: i2c: samsung: do not put a default class for the adapter

CHROMIUM: i2c: samsung: do not put a default class for the adapter

Avoid adding I2C_CLASS_HWMON and I2C_CLASS_SPD class flags to all
Samsung I2C adapters when the I2C mappings are defined in a device tree.
So the drivers doing an auto-detection by probing busses won't mess-up
sensitive I2C devices or trigger long timeouts on non-functional busses.

Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
BUG=chrome-os-partner:16725
TEST=emerge-daisy_spring chromeos-kernel
On spring, run with LM90 driver compiled and do not see timeout at
startup on non-functional busses

Change-Id: Iacdba3846c59f605224ff61f5b7c605828486db3
Reviewed-on: https://gerrit.chromium.org/gerrit/42480
Reviewed-by: Olof Johansson <olofj@chromium.org>
Tested-by: Vincent Palatin <vpalatin@chromium.org>
Commit-Queue: Vincent Palatin <vpalatin@chromium.org>