avoid alignment of hairpin and dynamic text

[Werner LEMBERG]

How can I avoid the vertical alignment of a hairpin and a dynamic text
that starts or stops the hairpin?  For example, in this situation

  { f1\< | e''\p }

I want to make LilyPond position the `\p` independently of the the
crescendo – in particular, I don't want to fiddle with `padding`,
`extra-offset`, or something similar to move the `\p' up; LilyPond
already knows how to position the `\p` correctly.[*]

In other words, how can I influence where a `DynamicLineSpanner`
starts and end?


    Werner


[*] I need this for some special situations where vertical space is
    very limited.