system/gnu-unifont: Updated for version 12.1.0.4.

Performed checks:

1. According to the project's page on GNU Savannah (https://savannah.gnu.org/projects/unifont), there was a "glitch" during uploading to the GNU servers. Because of this, the tar.gz archive for this version is available from only one URL:

http://unifoundry.com/pub/unifont/unifont-12.1.04/unifont-12.1.04.tar.gz

Size:   20970589 bytes
MD5:    b227ac14cefc5c437d66572b0d139d7b
SHA256: 9b5520c72f2c6018ce24ce8e55fe55aea2f52219565bbe2e265023491ef4adc0

2. Verified download signature.

3. Scanned download using ClamAV with latest virus databases.

4. Scanned download using VirusTotal:

First, I tried to scan the download URL using VirusTotal:

https://www.virustotal.com/gui/url/4a81d9dfb2920a2745ce06c3cb1a786ad8028a11f6b773949dce410ae665a722/detection

However, VirusTotal reports error 500 when trying to download the package. So, eventually, I decided to upload it manually:

https://www.virustotal.com/gui/file/9b5520c72f2c6018ce24ce8e55fe55aea2f52219565bbe2e265023491ef4adc0/summary