YJIT: Fix assert in OOM scenario

We still need to do `jit.record_boundary_patch_point = false`
when gen_outlined_exit() returns `None` and we return with `?`.
Previously, we tripped the assert at codegen.rs:1042.

Found with `--yjit-exec-mem-size=3` on the lobsters benchmark.

Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
Co-authored-by: Maxime Chevalier-Boisvert <maxime.chevalierboisvert@shopify.com>

yjit/src/codegen.rs

@@ -853,10 +853,10 @@ fn jump_to_next_insn(
 
     // We are at the end of the current instruction. Record the boundary.
     if jit.record_boundary_patch_point {
+        jit.record_boundary_patch_point = false;
         let exit_pc = unsafe { jit.pc.offset(insn_len(jit.opcode).try_into().unwrap()) };
         let exit_pos = gen_outlined_exit(exit_pc, &reset_depth, ocb);
         record_global_inval_patch(asm, exit_pos?);
-        jit.record_boundary_patch_point = false;
     }
 
     // Generate the jump instruction