[patch] Fix ruby2[123] plist for CAPIDOCS set

[Eygene Ryabinkin]

Gentlemen, good day.

The patch at
  http://codelabs.ru/fbsd/ports/patches/ruby-22-23-fix-CAPI-plist.patch
fixes CAPIDOCS case for the current Ruby ports.  Checked its applicability
to all current on/off combination of doc-related knobs (CAPIDOCS/DOCS/RDOC).

OK to commit?
-- 
Eygene Ryabinkin                                        ,,,^..^,,,
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