OpenBSD devel/boehm-gc: update to 8.2.4

[Ivan Maidanski]

Dear colleagues,
 
Could you please update devel/boehm-gc from upstream?
Upstream tarballs:
*  https://github.com/ivmai/bdwgc/releases/download/v8.2.4/gc-8.2.4.tar.gz  ( 
sha256: 3d0d3cdbe077403d3106bb40f0cbb563413d6efdbb2a7e1cd6886595dec48fc2 )
*  
https://github.com/ivmai/libatomic_ops/releases/download/v7.8.0/libatomic_ops-7.8.0.tar.gz
  ( sha256: 15676e7674e11bda5a7e50a73f4d9e7d60452271b8acf6fd39a71fefdf89fa31 )
 
I have prepared a patch (for MidnightBSD, might be useful to you):  
https://github.com/MidnightBSD/mports/pull/93/commits/61a2239e6fb3b2b65cfa8e45c736a41a8d3433d0
 
Thank you.
 
[1]  https://openports.pl/path/devel/boehm-gc
[2]  http://cvsweb.openbsd.org/cgi-bin/cvsweb/ports/devel/boehm-gc/
[3]  https://github.com/openbsd/ports/blob/master/devel/boehm-gc/distinfo
 
Regards,
Ivan