util/log: Pass Error pointer to qemu_set_log

Do not force exit within qemu_set_log; return bool and pass
an Error value back up the stack as per usual.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-5-richard.henderson@linaro.org>

scsi/qemu-pr-helper.c

@@ -1001,7 +1001,7 @@ int main(int argc, char **argv)
         exit(EXIT_FAILURE);
     }
     trace_init_file();
-    qemu_set_log(LOG_TRACE);
+    qemu_set_log(LOG_TRACE, &error_fatal);
 
 #ifdef CONFIG_MPATH
     dm_init();