Attributes 'suffix' and 'allowClear' of component 'Input' is sometime conflicted

[thisrabbit]

• I have searched the issues of this repository and believe that this is not a duplicate.

Reproduction link

Steps to reproduce

1. Type something on both input component so that the clear icon can show up;

What is expected?

The position of clear button in the second input component will be exactly the same with the first input component.

What is actually happening?

The position of clear button in the second input component is wrong.

Environment	Info
antd	3.21.2
React	16.8.6
System	Windows 10
Browser	Chrome 76

---

I actually want to create an input component with maximum input length hint, so I put the number in the suffix attribute, but it seems that the clear button only work correctly when the suffix is an icon. I also recommend you guys support the maximum length hint feature because it's useful when developer need to restrain the length user typed in!

[afc163]

same as #17414

[thisrabbit]

Sorry for duplicate :)