MFC r304953:
Define ipfilter's SOLARIS macro in a defined and portable way.
Reviewed by: cy
Differential Revision: https://reviews.freebsd.org/D7671
MFC r304959 (by kib):
Complete r304953.
Sponsored by: The FreeBSD Foundation
MFC r304964:
Follow-up to r304953, in which I broke the build: apparently the SOLARIS
macro is defined in lots of different places in ipfilter, so replace all
of the nonportable definitions with portable ones.
Pointy hat to: dim