The last two lines of the current ebuild are obsolte, because make install already puts images/AudacityLogo48x48.xpm in position as /usr/share/audacity/audacity.xpm. As the two icons go in the same place it doesn't matter, but the ebuild could be simplified as in the following patch
Created attachment 137407 [details, diff] Patch to simplify ebuild
fixed, thanks, I hadnt noticed it wasnt needed anymore