wifi: ath12k: refactor REO CMD ring handling

wifi: ath12k: refactor REO CMD ring handling

The entry of REO CMD ring of existing chips has a 64 bit TLV header, hence
below functions take a 64 bit TLV assumption by default

        ath12k_wifi7_hal_reo_init_cmd_ring()
        ath12k_wifi7_hal_reo_cmd_queue_stats()
        ath12k_wifi7_hal_reo_cmd_flush_cache()
        ath12k_wifi7_hal_reo_cmd_update_rx_queue()

However this is not the case for QCC2072 of which the TLV is 32 bit,
meaning above functions don't work for it.

Rename/refactor above functions to prepare for QCC2072 support:

Rename the first one to ath12k_wifi7_hal_reo_init_cmd_ring_tlv64() to
better reflect what it is doing. There will be a 32 bit variant when
QCC2072 support is in place.

For the last ones, remove TLV length assumption and offload TLV encoding
work to a newly added callback _reo_cmd_enc_tlv_hdr. This way each chip
can register its own handler hence can do the work accordingly.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00302-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.115823.3

Signed-off-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20260112-ath12k-support-qcc2072-v2-2-fc8ce1e43969@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>