NzFormControl: allow to customize validation status icon

What problem does this feature solve?

In our application clearing inputs are done by 'close-circle' icon at the end of input. This decision is based of user habit. When input has an error it is misleading to have 2 same icons. We would like to customize validation status icon.

What does the proposed API look like?

It can be similiar to customizing validation tip:

[nzSuccessIcon]="customSuccessIcon"
[nzWarningIcon]="customWarningIcon"
[nzErrorIcon]="customErrorIcon"
[nzValidatingIcon]="customValidatingIcon"

All of the inputs should be type TemplateRef | undefined

Optional solution could be to have just one input:

[nzStatusIcon]="customStatusIcon"

Which should be type TemplateRef<{$implicit: 'success' | 'error' | 'warning' | 'validating' | null}> | undefined

In both cases if input is undefined it should fallback to current behavior