Missing functions of fchdir.c in libpoke.a

[Hannes Domani]

Hello



When I was trying the gdb poke integration, I already failed in the configure 
step.
The configure test was this file:
```
char pk_register_iod ();
int
main ()
{
return pk_register_iod ();
  ;
  return 0;
}
```

Compiling fails like this:

$ gcc -o conftest.exe -g -O2 -I/gdb/gdb-libs64/include conftest.c 
-L/gdb/gdb-libs64/lib -lpoke -lgc
c:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe:
 C:/gdb/gdb-libs64/lib/libpoke.a(libgnu_la-close.o): in function `rpl_close':
C:\src\repos\poke\poke.git-build\gl-libpoke/../../../poke.git/gl-libpoke/close.c:71:
 undefined reference to `_gl_unregister_fd'
c:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe:
 C:/gdb/gdb-libs64/lib/libpoke.a(libgnu_la-fstat.o): in function `rpl_fstat':
C:\src\repos\poke\poke.git-build\gl-libpoke/../../../poke.git/gl-libpoke/fstat.c:73:
 undefined reference to `_gl_directory_name'
c:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe:
 C:/gdb/gdb-libs64/lib/libpoke.a(libgnu_la-open.o): in function `rpl_open':
C:\src\repos\poke\poke.git-build\gl-libpoke/../../../poke.git/gl-libpoke/open.c:171:
 undefined reference to `_gl_register_fd'
c:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe:
 C:/gdb/gdb-libs64/lib/libpoke.a(libgnu_la-dup2.o): in function `rpl_dup2':
C:\src\repos\poke\poke.git-build\gl-libpoke/../../../poke.git/gl-libpoke/dup2.c:186:
 undefined reference to `_gl_register_dup'
c:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe:
 C:/gdb/gdb-libs64/lib/libpoke.a(libgnu_la-fcntl.o): in function `dupfd':
C:\src\repos\poke\poke.git-build\gl-libpoke/../../../poke.git/gl-libpoke/fcntl.c:164:
 undefined reference to `_gl_register_dup'
collect2.exe: error: ld returned 1 exit status


All of these function calls are inside an #if REPLACE_FCHDIR block, but
fchdir.c itself was not compiled into libpoke.a.


Regards
Hannes