graphics/libdssim: drop in favor of CARGO_CRATES

$ cat /usr/local/include/dssim/dssim.h

#define DSSIM_MAJOR 2
#define DSSIM_MINOR 11
#define DSSIM_PATCH 3

#include <cstdarg>
#include <cstdint>
#include <cstdlib>
#include <new>

$ nm -D /usr/local/lib/libdssim.so

w _Jv_RegisterClasses
U _Unwind_GetDataRelBase
U _Unwind_GetIPInfo
U _Unwind_GetLanguageSpecificData
U _Unwind_GetRegionStart
U _Unwind_GetTextRelBase
U _Unwind_SetGR
U _Unwind_SetIP
w __cxa_finalize

0000000000003920 T rust_eh_personality

$ cat /usr/local/libdata/pkgconfig/dssim.pc
prefix=/usr/local
exec_prefix=${prefix}
libdir=${exec_prefix}/lib
includedir=${prefix}/include

Name: dssim
Description: Tool that measures structural similarity between images using a multi-scale variant of the SSIM algorithm.
Version: 2.11.3
Libs: -L${libdir} -ldssim
Cflags: -I${includedir}/dssim
Libs.private: -lexecinfo -lpthread -lgcc_s -lc -lm -lrt -lpthread -lutil -lutil