Mark PFDEBUG as write command in the commands table.

It is safer since it is able to have side effects.

src/redis.c

@@ -274,7 +274,7 @@ struct redisCommand redisCommandTable[] = {
     {"pfadd",pfaddCommand,-2,"wm",0,NULL,1,1,1,0,0},
     {"pfcount",pfcountCommand,2,"w",0,NULL,1,1,1,0,0},
     {"pfmerge",pfmergeCommand,-2,"wm",0,NULL,1,-1,1,0,0},
-    {"pfdebug",pfdebugCommand,-3,"r",0,NULL,0,0,0,0,0}
+    {"pfdebug",pfdebugCommand,-3,"w",0,NULL,0,0,0,0,0}
 };
 
 struct evictionPoolEntry *evictionPoolAlloc(void);