slim_ngd: Use QMI server up notification instead of APR for probing

Slimbus QMI-server can reside on any other remote processor.
Avoid depedency on APR (for APR state) by utilizing QMI server-up
notification for slimbus hardware initialization from apps processor.

Change-Id: I85e268d08e5c4cfc9c53513199784813200f0223
Signed-off-by: Sagar Dharia <sdharia@codeaurora.org>
Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>