ports-mgmt/portlint: Update to 2.20.0

• Check for duplicate distinfo items [1]
• Remove vestiges of SVN [2]

[2] Switch to using git status to determine if a file is under git version
control. Also, PL_SVN_IGNORE has been renamed to PL_GIT_IGNORE.

PR: 267168 [1]

		267145 [2]

Submitted by: rodrigo [1]
Thanks to: pauamma for the git status command [2]