wlan: fix wrong indexing of WDI_RATE_UPDATE_IND

Fixes the wrong indexing of WDI_RATE_UPDATE_IND.

Change-Id: I71639ee99e2a3d3a824947a6b94f20fecddcbb07
CRs-Fixed: 620661
wlan: Release 3.2.3.252a

Release 3.2.3.252a

Change-Id: I149df6e5270522b234b57d3055a9b265a68e0960