[WCNCR00166654] misc: add memory preallocation module

[Description]
memory preallocation is for avoiding memory fragmentation

Usage:
1. in Makefile.x86 or Makefile.ce
   export CONFIG_MTK_PREALLOC_MEMORY=y
2. after build, there is preallocate module
   ex. wlan_mt6632_usb_prealloc.ko
3. insmod prealloc module before insmod wifi module

Note:
for all HIFs, now just USB is implemented

Test:
in Linux PC is ok
1. insmod prealloc module
2. loop insmod wifi module -> connect AP -> rmmod wifi module

Change-Id: I3531381a328ee47f25e2cd2764b67e1dbfe04578
Signed-off-by: Neil Chen <yn.chen@mediatek.com>
CR-Id: WCNCR00166654
Feature: misc
8 files changed