CMake: clang lto: enable other vtable-related opts.
CMake: clang lto: enable other vtable-related opts.

Tests pass, perf change within noise, mostly.

darktable-org/rawspeed,darktable-org/rawspeed,darktable-org/rawspeed,LebedevRI/rawspeed,darktable-org/rawspeed,LebedevRI/rawspeed,LebedevRI/rawspeed,LebedevRI/rawspeed,LebedevRI/rawspeed,darktable-org/rawspeed