tcg: Use the GDB JIT debugging interface.

This allows us to generate unwind info for the dynamicly generated
code in the code_gen_buffer.  Only i386 is converted at this point.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/exec.c b/exec.c
index 265e895..6731ab8 100644
--- a/exec.c
+++ b/exec.c
@@ -636,6 +636,7 @@
     cpu_gen_init();
     code_gen_alloc(tb_size);
     code_gen_ptr = code_gen_buffer;
+    tcg_register_jit(code_gen_buffer, code_gen_buffer_size);
     page_init();
 #if !defined(CONFIG_USER_ONLY) || !defined(CONFIG_USE_GUEST_BASE)
     /* There's no guest base to take into account, so go ahead and