bio: remove reference count.

It appears that this reference “count” is set to one at creation and
never touched after that.

Change-Id: I3238a6d3dd702953771b8ec725c1c5712c648fba
Reviewed-on: https://boringssl-review.googlesource.com/4320
Reviewed-by: Adam Langley <agl@google.com>
2 files changed