staging: prima: setup wcnss before prima loads

* Prima needs wcnss to be set up when it loads.
  Therefore use a platform_driver to notify prima that wcnss is ready.

This commit is largely based on "staging: prima: Allow prima_wlan to be
built inside kernel" (I6c403f705e9dffa524a2aab54453e50775b45264), but
changes to wcnss are already included in this kernel. Also, this commit
includes a couple more modname changes. Reference the original commit
for a better understanding of how this is implemented.

Change-Id: I1d20cec90b446c9318b8a13143ac21ff33d2acec