Fix bool column corruption with ORC Reader (#7483)

Since there was a possibility that only partial set of bits would be read in case the values are buffered, the max_vals had to be rounded-off to higher next byte.

closes #7345

Authors:
  - Ram (Ramakrishna Prabhu) (@rgsl888prabhu)

Approvers:
  - Vukasin Milovanovic (@vuule)
  - Devavret Makkar (@devavret)

URL: #7483

cpp/src/io/orc/stripe_data.cu

@@ -1572,7 +1572,7 @@ __global__ void __launch_bounds__(block_size)
           if (t == 0) { s->top.data.buffered_count = n; }
         }
 
-        numvals = min(numvals * 8, is_last_set ? s->top.data.max_vals : blockDim.x);
+        numvals = min(numvals * 8, is_last_set ? (s->top.data.max_vals + 7) & (~0x7) : blockDim.x);
 
       } else if (s->chunk.type_kind == LONG || s->chunk.type_kind == TIMESTAMP ||
                  s->chunk.type_kind == DECIMAL) {