ompi/mca/btl/openib: Fix memory leak and accessing free'd memory issues
Let imagine that we have two btls in btl_openib_component_init() both points to the same openib_btl->device and as a result have the same openib_btl->device->endpoints array.

Finalization phase calls twice mca_btl_openib_finalize()->mca_btl_openib_finalize_resources().
mca_btl_openib_finalize_resources() frees endpoint related btl. But the second call of mca_btl_openib_finalize_resources() checks endpoint that is released by previus call.

fixed by Igor, reviewed by miked/vasily
cmr=v1.7.4:reviewer=ompi-gk1.7