ath10k: move non-fatal warn logs to dbg level

During driver load below warn logs are printed in the console if
firmware doesn't support some optional HTC services, ex:pktlog.
It is likely some older fw version may not support PKTLOG HTC
service as legacy fw uses HTC DATA service  for pktlog.
Move this log to debug level to remove un-necessary warn message
on console.

htc.c:803:  ath10k_warn(ar, "unsupported HTC service id: %d\n",
htc.c:881:  ath10k_warn(ar, "unsupported HTC service id: %d\n",

Signed-off-by: Govind Singh <govinds@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>