shader: drop the duplicate-use scan from Inst::AddUse

src/graphics/shader/recompiler/ir/Value.cpp

@@ -256,9 +256,6 @@ void Inst::Invalidate() {
 }
 
 void Inst::AddUse(Inst* used, size_t operand) {
-	const auto found = std::ranges::find_if(
-	    used->uses, [&](const Use& use) { return use.user == this && use.operand == operand; });
-	EXIT_IF(found != used->uses.end());
 	used->uses.push_back({this, operand});
 }