Revert "DatePicker: input display style changes to block, fixed #2018"

[baiyaaaaa]

This reverts commit b3095a7.

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[QingWei-Li]

歪？

[baiyaaaaa]

按照原生的控件看输入框应该是 inline-block 才对，应该修改的是 input 的为 inline-block，
换个角度看，像日期这种输入框肯定不是用户默认想要的，因为值的长度是固定的，有一个默认能比较适合的展示 value 的宽度肯定是更好的选择。

[QingWei-Li]

所以 select 也要改咯？

[baiyaaaaa]

滋瓷 select 和 input 改过来