pvq: drop unused declaration

Change-Id: I5d95bb897d335dc17aa0ae5e873ba7dee46c6fda

av1/common/pvq.h

diff --git a/av1/common/pvq.h b/av1/common/pvq.h
index a5051b4..371e4bd 100644
--- a/av1/common/pvq.h
+++ b/av1/common/pvq.h
@@ -16,7 +16,6 @@
 # include "generic_code.h"
 # include "odintrin.h"
 
-extern const double *OD_BASIS_MAG[2][OD_NBSIZES + 1];
 extern const int OD_QM8_Q4_FLAT[];
 extern const int OD_QM8_Q4_HVS[];