Bug#796310: libgraphicsmagick3: --with-quantum-depth=16 breaks ABI

[Emilio Pozuelo Monfort]

reassign 796310 src:graphicsmagick 1.3.20-4
fixed 796310 src:graphicsmagick 1.3.21-4
thanks

Hi,

Since libgraphicsmagick3 no longer exists, the BTS gets confused and thinks this
bug isn't fixed, and so britney won't attempt to migrate graphicsmagick:

    Updating libgraphicsmagick3 introduces new bugs: #796310

Let's see if this fixes that.

Emilio