device: Rename config_info attribute to config

There use to be a config attribute of type device_config, on which
config_info could be found. config_info was thus named that way to
differentiate easily from config attribute in struct device.

Now that there is no such device_config structure, config_info in
structure device now, can be renamed to config.

Semantically, it makes for sense. We have an attribute pointing to the
configuration of the device driver instance. Configuration information
is correct but has a redundant meaning.

Fixes #27397

Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>