[jak 2] ETIE (#2326)

Definitely needs a clean up pass, but I think the functionality is very
close.

There's a few "hacks" still:
- I am using the emerc logic for environment mapping, which doesn't care
about the length of the normals. I can't figure out how the normal
scaling worked in etie. I want to do a little bit more experimentation
with this before merging.
- There is some part about adgifs for TIE and ETIE that I don't
understand. The clearly correct behavior of TIE/ETIE is that the alpha
settings from the adgif shader are overwritten by the settings from the
renderer. But I can't figure out how this happens in all cases.
- Fade out is completely disabled. I think this is fine because the
performance difference isn't bad. But if you are comparing screenshots
with PCSX2, it will make things look a tiny bit different.

decompiler/VuDisasm/VuDisassembler.cpp

@@ -225,6 +225,8 @@ VuDisassembler::VuDisassembler(VuKind kind) : m_kind(kind) {
   add_op(VuInstrK::SQRT, "sqrt").fsf_zero().ftf_0().vis_zero().dst_q().src_vft();
   add_op(VuInstrK::SQD, "sqd").dst_mask().src_vfs().src_vit();
   add_op(VuInstrK::ERLENG, "erleng").dst_mask().vft_zero().src_vfs().dst_p();
+  add_op(VuInstrK::ESUM, "esum").dst_mask().vft_zero().src_vfs().dst_p();
+  add_op(VuInstrK::ESADD, "esadd").dst_mask().vft_zero().src_vfs().dst_p();
   add_op(VuInstrK::ELENG, "eleng").dst_mask().vft_zero().src_vfs().dst_p();
   add_op(VuInstrK::MFP, "mfp").dst_mask().dst_vft().src_p();
 }
@@ -294,10 +296,14 @@ VuInstrK VuDisassembler::lower_kind(u32 in) {
         return VuInstrK::XTOP;
       case 0b11011'1111'00:
         return VuInstrK::XGKICK;
+      case 0b11100'1111'00:
+        return VuInstrK::ESADD;
       case 0b11100'1111'10:
         return VuInstrK::ELENG;
       case 0b11100'1111'11:
         return VuInstrK::ERLENG;
+      case 0b11101'1111'10:
+        return VuInstrK::ESUM;
       case 0b11110'1111'11:
         return VuInstrK::WAITP;
     }