[PICA] Implement SLTI

include/PICA/shader.hpp

@@ -23,6 +23,7 @@ namespace ShaderOpcodes {
 		RSQ = 0x0F,
 		MOVA = 0x12,
 		MOV = 0x13,
+		SLTI = 0x1B,
 		NOP = 0x21,
 		END = 0x22,
 		CALL = 0x24,
@@ -111,6 +112,7 @@ class PICAShader {
 	void mul(u32 instruction);
 	void rcp(u32 instruction);
 	void rsq(u32 instruction);
+	void slti(u32 instruction);
 
 	// src1, src2 and src3 have different negation & component swizzle bits in the operand descriptor
 	// https://problemkaputt.github.io/gbatek.htm#3dsgpushaderinstructionsetopcodesummary in the