Undo the disaster that was the patch to unicorn github issue #266 and fix it correctly. makes normal self-modifying code work.

qemu/target-sparc/translate.c

@@ -5421,6 +5421,7 @@ static inline void gen_intermediate_code_internal(SPARCCPU *cpu,
     if (!env->uc->block_full && HOOK_EXISTS_BOUNDED(env->uc, UC_HOOK_BLOCK, pc_start)) {
         // save block address to see if we need to patch block size later
         env->uc->block_addr = pc_start;
+        env->uc->size_arg = tcg_ctx->gen_opparam_buf - tcg_ctx->gen_opparam_ptr + 1;
         gen_uc_tracecode(tcg_ctx, 0xf8f8f8f8, UC_HOOK_BLOCK_IDX, env->uc, pc_start);
     }