libbarrelfish: Moved cap_destroy() into error case in span_domain_reply.
libbarrelfish: Moved cap_destroy() into error case in span_domain_reply.

mslovy/barrelfish,kishoredbn/barrelfish,8l/barrelfish,linusyang/barrelfish,BarrelfishOS/barrelfish,utsav2601/cmpe295A,kishoredbn/barrelfish,BarrelfishOS/barrelfish,8l/barrelfish,mslovy/barrelfish,BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,utsav2601/cmpe295A,BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,mslovy/barrelfish,linusyang/barrelfish,kishoredbn/barrelfish,linusyang/barrelfish,utsav2601/cmpe295A,mslovy/barrelfish,utsav2601/cmpe295A,mslovy/barrelfish,8l/barrelfish,linusyang/barrelfish,linusyang/barrelfish,kishoredbn/barrelfish,8l/barrelfish,BarrelfishOS/barrelfish,kishoredbn/barrelfish,BarrelfishOS/barrelfish,kishoredbn/barrelfish,8l/barrelfish,utsav2601/cmpe295A,utsav2601/cmpe295A,mslovy/barrelfish,8l/barrelfish