graphics/graphviz port test failure

[chukharev at mail.ru]

The 'port test' command (ports-mgmt/porttools) tests a port for a number of possible errors
by running portlint, building, packaging, installing, and de-installing with a check for
left files. This is done with defined PREFIX and PKG_DBDIR variables. 'port test' command
is recommended by the Porter's Handbook.

Note that the port installs the usual way.

When running 'port test' command in graphics/graphviz, the following output is generated
indicating fatal errors from portlint.


graphics/graphviz
+++++++++++++++

===> Validating port with portlint
WARN: Makefile: [391]: use ${VARIABLE}, instead of $(VARIABLE).
FATAL: Makefile: [331]: USE_RUBY is set after including bsd.port.pre.mk.
WARN: Makefile: [213]: is USE_GNOME a user-settable option? Consider using WITH_GNOME instead.
WARN: Makefile: [217]: is USE_XORG a user-settable option? Consider using WITH_XORG instead.
WARN: Makefile: possible use of absolute pathname "/nonexistent".
WARN: Makefile: CFLAGS/CXXFLAGS are not needed in CONFIGURE_ENV as they are already added there in bsd.port.mk.
WARN: Makefile: only one MASTER_SITE configured.  Consider adding additional mirrors.
1 fatal error and 6 warnings found.
Error validating port