* guile-ltdl.h: main header file for guile's internal

* guile-ltdl.h: main header file for guile's internal
libguile-ltdl.

* raw-ltdl.c: Remove custom realloc. (#define rpl_realloc
realloc).  You can't define realloc like this unless you also
define malloc.  This is a quick hack for now; we may want
something cleaner later.
(memcpy): coerce ptrs to (char *) before copying characters
through them -- I can't recall for sure, but I believe this was
causing an overrun error at times.
(realloc): commented out -- as mentioned above, you can't define
your own malloc unless you know enough about the malloc in use to
be able to tell how big the src ptr is.  The disabled code
incorrectly used the *destination* ptr to decide how much to copy.
This sometimes results in out-of-bound accesses which cause
segfaults.
(tryall_dlopen_module): check to be sure (dirname_len > 0) before
testing first character against '/'.
(try_dlopen): check for feof(file) in read loop -- otherwise
infloop?
(scm_lt_dlopenext): remove unused variable file_found.
(LT_EOS_CHAR): moved here from guile-ltdl.h.