cnss2: Add a 128kB to prealloc pool

WLAN host driver has a new memory requirement for regulatory structure
allocation of order 5. Increase 128 kB slot by one.

Change-Id: If95291c96df0b7588b54f8e19b287d846896b479
Signed-off-by: Mahesh Kumar Kalikot Veetil <mkalikot@codeaurora.org>