leave certificate name untouched in decode()

[vladak]

When running mk-ca-bundle.pl with the -v option, it fails to report the certificate name. This is happening due to the decode() call from Encode module having CHECK set without the Encode::LEAVE_SRC bit.

https://perldoc.perl.org/Encode.html#LEAVE_SRC says:

If the Encode::LEAVE_SRC bit is not set but CHECK is set, then the source string to encode() or decode() will be overwritten in place. If you're not interested in this, then bitwise-OR it with the bitmask.

This simple change adds the bit and also reports skipped certificates (which is handy in the light of https://www.imperialviolet.org/2012/01/30/mozillaroots.html).

Thank you.

[bagder]

Thanks!