www/node6: Update 6.10.3 -> 6.11.0

[bhughes]

Summary

www/node6: Update 6.10.3 -> 6.11.0

While here, sort ONLY_FOR_ARCHS as recommended by portlint.

Approved by: robak (mentor)

Test Plan

$ pwd
/usr/ports/www/node6
$ portlint -C
WARN: Makefile: [0]: possible direct use of command "python" found. use ${PYTHON_CMD} instead.
WARN: Makefile: possible use of absolute pathname "/etc/make.conf".
0 fatal errors and 2 warnings found.

poudriere build logs:
http://35.176.84.170/data/103amd64-default/2017-06-13_19h58m42s/logs/node6-6.11.0.log
http://35.176.84.170/data/103i386-default/2017-06-13_20h02m19s/logs/node6-6.11.0.log
http://35.176.84.170/data/110amd64-default/2017-06-13_20h06m00s/logs/node6-6.11.0.log
http://35.176.84.170/data/110i386-default/2017-06-13_20h10m06s/logs/node6-6.11.0.log
http://35.176.84.170/data/111amd64-default/2017-06-13_20h14m16s/logs/node6-6.11.0.log
http://35.176.84.170/data/111i386-default/2017-06-13_20h18m49s/logs/node6-6.11.0.log
http://35.176.84.170/data/120amd64-default/2017-06-13_20h23m25s/logs/node6-6.11.0.log
http://35.176.84.170/data/120i386-default/2017-06-13_20h29m29s/logs/node6-6.11.0.log

[bhughes]

Ping, any chance I could get this reviewed? Thanks :)

[robak]

The reports of my death are greatly exaggerated. LGTM.