icnss: Changes to avoid multiple registration for pdr

Service locator parses modem jsn file and knows where wlan
service is running. If multiple jsn files are present with
same entries platform driver registers to pdr notifier for
same service multiple times. So, add changes to avoid
multiple registration for same service.

Change-Id: I815ca92ea5ad4ae67c54f52bf2ae101919719831
Signed-off-by: Sandeep Singh <sandsing@codeaurora.org>