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