[Tails-l10n] (Review) [de] mac_spoofing.de.po

Hi,
I just translated:
wiki/src/doc/first_steps/startup_options/mac_spoofing.de.po in the
branch "mac_spoof".

My git is: https://github.com/spriver/tails

I hope it is okay that I changed the term "MAC address spoofing" into
"Verschleiern der MAC-Adresse"


Regards,

spriver