Geo: output 10 chars of geohash, not 11.

This does not limit the actual precision, because the last digit bits were
garbage, and the shift value became even negative in the last iteration.

src/geo.c

@@ -734,14 +734,14 @@ void geohashCommand(client *c) {
             r[1].max = 90;
             geohashEncode(&r[0],&r[1],xy[0],xy[1],26,&hash);
 
-            char buf[12];
+            char buf[11];
             int i;
-            for (i = 0; i < 11; i++) {
+            for (i = 0; i < 10; i++) {
                 int idx = (hash.bits >> (52-((i+1)*5))) & 0x1f;
                 buf[i] = geoalphabet[idx];
             }
-            buf[11] = '\0';
-            addReplyBulkCBuffer(c,buf,11);
+            buf[10] = '\0';
+            addReplyBulkCBuffer(c,buf,10);
         }
     }
 }