It doesn't seem like the BTL was using uninitialized pointer. But simply
setting the rcache pointer to NULL after destroying it makes the valgrind
errors go away.
Fixes Issue #6345
Signed-off-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@intel.com>
(cherry picked from commit 786e686d4347655b574e609c65626c8323bb49b2)
Signed-off-by: Brian Barrett <bbarrett@amazon.com>
0d2a0b1568