Release rw_sema properly when block allocator runs out of memory and returns error. Change-Id: I6b7cf9564ae25ad1ba30edfcb1ae8a20cf7dc9db Signed-off-by: Konsta Holtta <kholtta@nvidia.com> Reviewed-on: http://git-master/r/601792 Reviewed-by: Automatic_Commit_Validation_User GVS: Gerrit_Virtual_Submit Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>