wifi: ath11k: clear shared SRNG pointer state on restart

wifi: ath11k: clear shared SRNG pointer state on restart

LMAC rings reuse the shared rdp/wrp pointer buffers without going
through the normal SRNG hw-init path that zeros non-LMAC ring
pointers. After restart, ath11k_hal_srng_clear() can therefore hand
stale hp/tp state from the previous firmware instance back to the new
one.

Clear the shared pointer buffers while keeping the allocations in
place so restart still avoids reallocating SRNG DMA memory, but starts
with fresh ring-pointer state.

Fixes: 32be3ca4cf78b ("wifi: ath11k: HAL SRNG: don't deinitialize and re-initialize again")
Cc: stable@vger.kernel.org
Closes: https://lore.kernel.org/all/CAOPSVF04q6uvVdq8GTRLHBrVMdpt9=o9wVcFMc6f-yhmSBcZqQ@mail.gmail.com/
Signed-off-by: Kyle Farnung <kfarnung@gmail.com>
Reviewed-by: Rameshkumar Sundaram <rameshkumar.sundaram@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Link: https://patch.msgid.link/20260513-kfarnung-ath11k-srng-clear-pointer-state-v1-1-bc700dd8b333@gmail.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>