wifi: ath12k: avoid dynamic alloc when parsing wmi tb

wifi: ath12k: avoid dynamic alloc when parsing wmi tb

On each WMI message received from the hardware, we alloc a temporary array
of WMI_TAG_MAX entries of type void *. This array is then populated with
pointers of parsed structs depending on the WMI type, and then freed. This
alloc can fail when memory pressure in the system is high enough.

Given the fact that it is scheduled in softirq with the system_bh_wq, we
should not be able to parse more than one WMI message per CPU at any time.

So instead lets move to a per cpu allocated array, that is reused across
calls. This memory is allocated as needed and refcounted to exist only
as long as one struct ath12k_base lives.

ath12k_wmi_tlv_parse_alloc() and ath12k_wmi_tlv_parse() are merged
together as it no longer allocs mem but returns the existing per-cpu one.

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.3.1-00218-QCAHKSWPL_SILICONZ-1

Signed-off-by: Nicolas Escande <nico.escande@gmail.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Rameshkumar Sundaram <rameshkumar.sundaram@oss.qualcomm.com>
Link: https://patch.msgid.link/20260407095426.3285574-1-nico.escande@gmail.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>