libgpg-error: po/ja.po update

[NIIBE Yutaka]

Hello,

I had opportunity to clone libgpg-error today, and I realized its
po/ja.po is outdated, also found some errors (it didn't recognize
"pinentry" as a program name, it misunderstood MAC as Media Access
Control, instead of Message Authentication Code, etc.).

I have updated it.  Since I don't think it's maintained by
translation-team-ja at lists.sourceforge.net, I modified:

	"Language-Team: none\n".

I'll maintain this translation.

OK to commit?
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