LibJS/JIT: Compile the GetGlobal bytecode instruction

Author: https://github.com/awesomekling
Commit: 3974ce2069
Pull-request: https://github.com/SerenityOS/serenity/pull/21619
Reviewed-by: https://github.com/Hendiadyoin1

Userland/Libraries/LibJS/JIT/Compiler.h

@@ -55,6 +55,7 @@ private:
     void compile_new_string(Bytecode::Op::NewString const&);
     void compile_get_by_id(Bytecode::Op::GetById const&);
     void compile_get_by_value(Bytecode::Op::GetByValue const&);
+    void compile_get_global(Bytecode::Op::GetGlobal const&);
 
     void store_vm_register(Bytecode::Register, Assembler::Reg);
     void load_vm_register(Assembler::Reg, Bytecode::Register);