Change Details

Proposed commit log message: ``` misc/mbuffer: Update to 20210328 - Update to 20210328 - Switch to USES=autoreconf gmake instead of patching configure and Makefile.in - Take maintainership Reviewed_by: koobs Approved by: koobs (ports, mentor) Differential_Revision: D30338 MFH: No (catch up with upstream new release) ```

``` misc/mbuffer: Update to 20210328 - Update to 20210328 - Switch to USES=autoreconf gmake instead of patching configure and Makefile.in - Take maintainership Reviewed_by: koobs Approved by: koobs (ports, mentor, implicit) Differential_Revision: D30338 MFH: No (feature release) ```

Proposed commit log message: ``` misc/mbuffer: Update to 20210328 - Update to 20210328 - Switch to USES=autoreconf gmake instead of patching configure and Makefile.in - Take maintainership Reviewed_by: koobs Approved by: koobs (ports, mentor, implicit) Differential_Revision: D30338 MFH: No (catch up with upstream newfeature release) ```