shader/node: Unpack bindless texture encoding

Bindless textures were using u64 to pack the buffer and offset from
where they come from. Drop this in favor of separated entries in the
struct.

Remove the usage of std::set in favor of std::list (it's not std::vector
to avoid reference invalidations) for samplers and images.

src/video_core/textures/texture.h

@@ -132,6 +132,8 @@ enum class SwizzleSource : u32 {
 };
 
 union TextureHandle {
+    TextureHandle(u32 raw) : raw{raw} {}
+
     u32 raw;
     BitField<0, 20, u32> tic_id;
     BitField<20, 12, u32> tsc_id;