Remove stat module & update lstat.

Remove stat module & update lstat.
* MODULES.html.sh (stat): Remove.
* MODULES.html: Regenerated.
* config/srclist.txt (GLIBC sources): Remove stat.
* lib/stat.c: Remove this file...
(slash_aware_lstat): ...moving this content and its support...
* lib/lstat.c (rpl_lstat): ...into here.
* lib/lstat.h: New file.
* m4/lstat.m4 (gl_FUNC_LSTAT): Drop AC_FUNC_LSTAT in favor of
AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK.
* m4/stat.m4: Remove this file.
* modules/lstat (Description): Correct function name.
(Files): Add "lstat.h".
(Depends-on): Remove stat, add xalloc, stat-macros.
* modules/stat: Remove this file.
(Include): Add "lstat.h", remove <sys/stat.h>.