Copying the The config.h from config.h.in didn't work and
resulted in errors like that:
    external/wipe/dir.c: In function 'drill_down':
    external/wipe/dir.c:92:17: warning:
    assignment from incompatible pointer type
       while ((entry = readdir(dir)) != NULL)
                     ^
    external/wipe/dir.c:94:24: error:
    dereferencing pointer to incomplete type
           if (strncmp(entry->d_name, ".", 2) && strncmp(entry->d_name, "..", 3) != 0)
                            ^
    external/wipe/dir.c:94:58: error:
    dereferencing pointer to incomplete type
           if (strncmp(entry->d_name, ".", 2) && strncmp(entry->d_name, "..", 3) != 0)
                                                              ^
    external/wipe/dir.c:95:15: error:
    dereferencing pointer to incomplete type
      do_file(entry->d_name); /*** process file ***/
                   ^
    external/wipe/dir.c: In function 'dir_sync':
    external/wipe/dir.c:299:36: warning:
    unused parameter 'name' [-Wunused-parameter]
     private int dir_sync(int ffd, char name[])
                                        ^
So it was generated on Parabola i686 by running ./configure.

Removing the errno declaration was also needed to make it
compile as otherwise we end up with errors like this one:
    In file included from external/wipe/blkdev.c:27:0:
    external/wipe/blkdev.c:66:12: error:
    conflicting types for '__errno'
     extern int errno;
                ^
    bionic/libc/include/errno.h:44:22: note:
    previous declaration of '__errno' was here
     extern volatile int* __errno(void) __pure2;
                          ^

Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>