qcacmn: Enable wbuff support for WMI

Register WMI with wbuff for pre-allocation of
skbs. Register at wmi_unified_attach() and
de-register at wmi wmi_unified_detach().

Change-Id: I9d6df1a8480324dd2a258de12672669a8fbe8940
CRs-Fixed: 2313935
3 files changed