os/bluestore/BlueStore: Removing dead code

os/bluestore/BlueStore: Removing dead code

This assignement of r is misleading. It does assign a value to r that is never
used by any code.

When the code runs into the while loop, r is always initialized again before any
usage. There isn't any direct jump to the "out" label making this value being
used as a return code.

When the code does exit this while loop, the r value is reassigned before being
used as a return code.

This makes this assignement useless and confusing. This patch simply remove this dead/useless code.

Signed-off-by: Erwan Velu <erwan@redhat.com>