Compilation issues for HASH_STATISTICS and HASH_DEBUG options

Dear hackers,

I found that postgres could not be built if a complier option HASH_STATISTICS is
set [1]. Also, I found HASH_DEBUG option caused warnings [2]. Usage of the are
mentioned at the code comments in dynahash.c.

I'm not sure whether we would keep supporting them because no one may not have
used anymore now.

Anyway, I tried to fix the error/warnings. Please see attached.

[1]:
```
dynahash.c: In function ‘hash_update_hash_key’:
dynahash.c:1178:9: error: ‘hctl’ undeclared (first use in this function)
 1178 |         hctl->accesses++;
      |         ^~~~
```

[2]:
```
dynahash.c: In function ‘init_htab’:
dynahash.c:779:68: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 12 has type ‘uint32’ {aka ‘unsigned int’} [-Wformat=]
  779 |         fprintf(stderr, "init_htab:\n%s%p\n%s%ld\n%s%ld\n%s%d\n%s%ld\n%s%u\n%s%x\n%s%x\n%s%ld\n",
      |                                                                  ~~^
      |                                                                    |
      |                                                                    long int
      |                                                                  %d
......
  784 |                         "MAX BUCKET      ", hctl->max_bucket,
      |                                             ~~~~~~~~~~~~~~~~        
      |                                                 |
      |
dynahash.c:779:86: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 18 has type ‘long int’ [-Wformat=]
  779 |    fprintf(stderr, "init_htab:\n%s%p\n%s%ld\n%s%ld\n%s%d\n%s%ld\n%s%u\n%s%x\n%s%x\n%s%ld\n",
      |                                                                                ~^
      |                                                                                 |
      |                                                                                 unsigned in
      |                                                                                %lx
......
  787 |                    "NSEGS           ", hctl->nsegs);
      |                                        ~~~~~~~~~~~                               
      |                                            |
      |                                            long int
dynahash.c:779:90: warning: format ‘%s’ expects a matching ‘char *’ argument [-Wformat=]
  779 |   fprintf(stderr, "init_htab:\n%s%p\n%s%ld\n%s%ld\n%s%d\n%s%ld\n%s%u\n%s%x\n%s%x\n%s%ld\n",
      |                                                                                   ~^
      |                                                                                    |
      |                                                                                    char *

dynahash.c:779:93: warning: format ‘%ld’ expects a matching ‘long int’ argument [-Wformat=]
  779 |   fprintf(stderr, "init_htab:\n%s%p\n%s%ld\n%s%ld\n%s%d\n%s%ld\n%s%u\n%s%x\n%s%x\n%s%ld\n",
      |                                                                                     ~~^
      |                                                                                       |
      |                                                                                       long int
```

Best regards,
Hayato Kuroda
FUJITSU LIMITED