cnss_prealloc: Add cnss_prealloc driver for WLAN

This is a snapshot of the cnss_prealloc driver and
associated files as of msm-4.9 commit:
commit 397a647228f4 ("icnss: remove pre-alloc memory
leak check in platform driver").

CRs-Fixed: 2073950
Change-Id: I06fbac7f0929e42ea3684537969013c430601e88
Signed-off-by: Yuanyuan Liu <yuanliu@codeaurora.org>