libsmb: Pass the correct path to cli_posix_stat()

libsmb: Pass the correct path to cli_posix_stat()

This fixes doing strlen() on talloc_tos(), about which valgrind is pretty
unhappy. Without this patch we survive the tests because we have fallbacks to
the non-posix flavors of stat(). With this patch in place cli_posix_stat()
becomes functional in this code path. This creates conflicts with the readdir
libsmbclient tests, which need fixing separately.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14101

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>