Those AFM files are not used anymore

They were used to build metrics for printer built in fonts, which was
dropped in the previous commit.

Change-Id: Id9fb3108facec61eb6de0a2d16546f1187465e50
Reviewed-on: https://gerrit.libreoffice.org/6861
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>