Forward supported flags to fstatat, this fixes issues like
using an empty path

Upstream BR: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=959876

Signed-off-by: Norbert Lange <nolange79@gmail.com>

diff -burN fakeroot-1.20.2.org/libfakeroot.c fakeroot-1.20.2/libfakeroot.c
--- fakeroot-1.20.2.org/libfakeroot.c	2014-10-05 17:16:00.000000000 +0200
+++ fakeroot-1.20.2/libfakeroot.c	2020-05-10 22:24:18.896625085 +0200
@@ -880,7 +880,7 @@
   /* If AT_SYMLINK_NOFOLLOW is set in the fchownat call it should
      be when we stat it. */
   INT_STRUCT_STAT st;
-  r=INT_NEXT_FSTATAT(dir_fd, path, &st, (flags & AT_SYMLINK_NOFOLLOW));
+  r=INT_NEXT_FSTATAT(dir_fd, path, &st, (flags & (AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH | AT_NO_AUTOMOUNT)));

   if(r)
     return(r);
@@ -1017,7 +1017,7 @@

   /* If AT_SYMLINK_NOFOLLOW is set in the fchownat call it should
      be when we stat it. */
-  r=INT_NEXT_FSTATAT(dir_fd, path, &st, flags & AT_SYMLINK_NOFOLLOW);
+  r=INT_NEXT_FSTATAT(dir_fd, path, &st, flags & (AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH | AT_NO_AUTOMOUNT));

   if(r)
     return(r);