security/ca_root_nss: Remove duplicate PLIST entry

These 2 files are already handled by @sample.

> Deinstalling for ca_root_nss

> Deinstalling ca_root_nss-3.93

Updating database digests format: 100%
Checking integrity... done (0 conflicting)
Deinstallation has been requested for the following 1 packages (of 0 packages in the universe):

Installed packages to be REMOVED:

ca_root_nss: 3.93

Number of packages to be removed: 1
[1/1] Deinstalling ca_root_nss-3.93...
[1/1] Deleting files for ca_root_nss-3.93: 11%
ca_root_nss-3.93: missing file /usr/local/etc/ssl/cert.pem
[1/1] Deleting files for ca_root_nss-3.93: 33%
ca_root_nss-3.93: missing file /usr/local/openssl/cert.pem
[1/1] Deleting files for ca_root_nss-3.93: 100%

Approved by: portmgr (blanket)