Remove av1_cost_coeffs from rdopt.h if using PVQ.
Remove av1_cost_coeffs from rdopt.h if using PVQ.

Change-Id: I08a2437e4eb2ef31ec7a675fba6bcec538019241

GrokImageCompression/aom,smarter/aom,GrokImageCompression/aom,GrokImageCompression/aom,luctrudeau/aom,GrokImageCompression/aom,smarter/aom,luctrudeau/aom,smarter/aom,luctrudeau/aom,smarter/aom,luctrudeau/aom,smarter/aom,GrokImageCompression/aom,GrokImageCompression/aom,smarter/aom,luctrudeau/aom,luctrudeau/aom