Robustness fix and license updates

• Update Makefile to use current version of GCC as defined in bsd.default-versions.mk. (USE_GCC=yes)
• Update Makefile with LICENSE and LICENSE_PERMS information and remove RESTRICTED and NO_CDROM (redundant)
• Update Makefile PORTREVISION

While here, pet portlint

PR: 243142
Submitted by: thomas@bsdunix.ch
Approved by: michael@fuckner.net (maintainer)