ath10k: setup peer UAPSD flag correctly

Setup UAPSD peer/peer rate flags correctly.
WMI_RC_UAPSD_FLAG is a peer rate capabilities flag
and should not be set as a peer flag.
Found during code review, doesn't fix a known
issues.

Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>