ath10k: request credit report if flow control enabled on ep

FW credit flow control is enabled for only WMI ctrl
service(CE3) but credit update is requested unconditionally
on all HTC services as part of HTC tx in CE3/CE0/CE4.

This is causing WOW failure as FW is not expecting credit
report request on other end-points(CE0/CE4).

Request credit report only on those endpoints where
credit flow control is enabled.

Testing:
    Tested on WCN3990 HW.
    Tested FW: WLAN.HL.2.0-01192-QCAHLSWMTPLZ-1.

Signed-off-by: Govind Singh <govinds@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Change-Id: I59307aa14cf62f303ab68bb5fd36fd89c081948b
Git-commit: c40e448e0bcf1541c0d0c42a197ef4f183a83db0
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/ath.git


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