This actually seems to be an issue with the clamav-daemon package:
Setting up clamav-daemon (0.98.6+dfsg-1ubuntu2) ...
/var/lib/dpkg/info/clamav-daemon.postinst: 626:
/var/lib/dpkg/info/clamav-daemon.postinst: cannot create : Directory nonexistent
dpkg: error processing package clamav-daemon (--c
Status changed to 'Confirmed' because the bug affects multiple users.
** Changed in: clamav (Ubuntu)
Status: New => Confirmed
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https://bugs.launchpad.net/bugs/1445
*** This bug is a duplicate of bug 1438745 ***
https://bugs.launchpad.net/bugs/1438745
** This bug has been marked a duplicate of bug 1438745
package clamav-daemon 0.98.6+dfsg-1ubuntu2 failed to install/upgrade:
subprocess installed post-installation script returned error exit status 2
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