sdm: Trigger validate upon lut swap.

drawcycle  N: Lut index: A   swap: 1
         N+1: Lut index: B   swap: 1
         N+2: Lut index: N/A swap: 1

In N+2 cycle, Qseed will not program Lut index and just sets
swap flag to set A. Triggering validate will result in resetting
if this flag in steady state.

CRs-Fixed: 2430749
Change-Id: Ia3117d3b201bad9ade679fb8e84904a16a94100b
3 files changed