For nvmem providers which have multiple instances, it is required
to suffix the provider name with proper id, so that they do not
confict for the same name. Currently the core does not handle
this case properly eventhough core already has logic to generate the id.

This patch add new devid type NVMEM_DEVID_AUTO for providers to be
able to allow core to assign id and append it to provier name.
Reported-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Link: https://lore.kernel.org/r/20200722100705.7772-8-srinivas.kandagatla@linaro.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>