Fix check-plist error

> Checking for pkg-plist issues (check-plist)

> Parsing plist

> Checking for items in STAGEDIR missing from pkg-plist

Error: Orphaned: @dir %%DOC_DIR%%

> Checking for items in pkg-plist which are not in STAGEDIR

> Error: Plist issues found.

• Error code 1

Stop.
make: stopped in /usr/ports/textproc/rubygem-cld3