py27 ports always show "new version available"

[Rob Belics]

I'm sure I caused this problem when FLAVORS came out by trying to set a
FLAVOR using "make". Using portmaster as I always have, py27-cffi and
py27-setuptools update to the latest version that portsnap downloads but
checking for new versions always returns "new version available" even after
updating.

 portmaster -L --index-only | egrep '(ew|ort) version|total install'
    ===>>> New version available: py27-cffi-1.11.2
    ===>>> New version available: py27-setuptools-38.2.5

Trying to remove the port with portmaster, pkg or 'make' and
reinstalling does not change anything.

FreeBSD 11.1 RELEASE p6