kernel 编译补遗

上回说到我的kernel能够启动了，不过还是有些问题。

一个是不断出modprobe: fatal: 说找不到.../modules.dep之类，而且一出就好几屏，上网搜了一下，也有人遇到这问题，不过好像他们都是不能启动，估计跟我情况不一样。后来经高人指点，原来我的kernel不用initrd, 于是make-kpkg时不要--initrd就好了（一开始没出initrd我还以为出bug了）

另外是声卡的问题，我查了下，并不是没认出声卡，而是多了dummy设备和virtual midi设备，我没查到如何配置alsa默认声卡，于是呼把这两个选项去了。

最后是说dma没打开，不知道为什么当时漏掉了，不过它还真是体贴，提醒了一下，要不然我以后慢的都不知道怎么回事。

最后基本就都正常了，跟原来比，启动是多了一点点错误信息，但是似乎不影响使用。

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