wifi: ath11k: move .max_tx_ring to struct ath11k_hw_hal_params

wifi: ath11k: move .max_tx_ring to struct ath11k_hw_hal_params

".max_tx_ring" is an upper bounds to indexing ".tcl2wbm_rbm_map". It
is initialized in, core.c, a different file than the array. This
spaghetti-like relation is fragile and not obvious. Accidentally
setting ".max_tx_ring" too high leads to a hard to track out-of-
bounds access and memory corruption.

There is a small ambiguity on the meaning of "max_tx_ring":
 - The highest ring, max=3 implies there are 4 rings (0, 1, 2, 3)
 - The highest number to use for array indexing (there are 3 rings)

Clarify this dependency by moving ".max_tx_ring" adjacent to the array
".tcl2wbm_rbm_map", and name it "num_tx_rings". Use ARRAY_SIZE()
instead of #defines to initialize the length field.

The intent is to make the code easier to understand rather than fix
an existing bug.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Link: https://patch.msgid.link/20251228151408.2116108-1-mr.nuke.me@gmail.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>