Log Message:
Drop dependency on libXp (from Imake)

* libXp was used by Xaw8, but it had been obsolated, and in pkgsrc,
  x11/libXaw/buildlink3.mk had been switched to pick up Xaw7 by default.
* With x11/xorg-cf-files, libXp was offered with XawClientLibs,
  but updated to 1.0.4, it was removed.
* And pkgsrc had been switched to use always xorg-cf-files and imake from pkgsrc,
  so all platforms should not require libXp from libXaw with Imake.

Bump PKGREVISION.