Clean up naming of VP9 support functions.

Change-Id: Ibfa931f3fb3a2ed2649733b7d7e679c0091dda90
diff --git a/scriptc/rs_iadst.rsh b/scriptc/rs_iadst.rsh
index dad396c..3208814 100644
--- a/scriptc/rs_iadst.rsh
+++ b/scriptc/rs_iadst.rsh
@@ -3,11 +3,11 @@
 
 #if RS_VERSION > 19
 
-extern void iadst4(const rs_allocation input, rs_allocation output, int32_t xoff);
+extern void rsIadst4(const rs_allocation input, rs_allocation output, int32_t xoff);
 
-extern void iadst8(const rs_allocation input, rs_allocation output, int32_t xoff);
+extern void rsIadst8(const rs_allocation input, rs_allocation output, int32_t xoff);
 
-extern void iadst16(const rs_allocation input, rs_allocation output, int32_t xoff);
+extern void rsIadst16(const rs_allocation input, rs_allocation output, int32_t xoff);
 
 #endif