Trivial fix of printing pointer

Qingqing Zhou <zhouqq@cs.toronto.edu> writes:

In spirit of incremental improvement, here is a trivial fix to use %p
instead %d to print pointer. -- maybe we should use context name better.

Actually, I wonder whether we shouldn't just get rid of these things
(CTX_printf/CTX1_printf) entirely; they seem fairly useless, especially
since most node types don't have 'em. Certainly if anyone had actually
*used* them in the past several years, there would have been some effort
to convert them to elog's instead of raw printf operations.

regards, tom lane