[gprof] disjoint histograms

[Nick Clifton]

Hi Ben,

>> My one suggested addition would be that you could add an entry in the 
>> binutils/NEWS file mentioning this new feature of gprof.
> 
> Perhaps even gprof.texi, if applicable?

I think both.  The NEWS files are used to make release notes for each 
new version of the binutils and I think that it would be nice to include 
a mention of Vladimir's new feature.

Cheers
   Nick