[patch] libiberty build-in-srcdir: ignore VPATH

[Michael Elizabeth Chastain]

I'm running into a simple problem with the ignore-VPATH patch.
libiberty/configure was not rebuilt from libiberty/configure.ac,
so it still has the old definition of @pexecute@.  My Makefile.in
looks like this:

  REQUIRED_OFILES = ... \
    ...
    ./partition.o ./physmem.o pex-unix.o \
    ...

And then Make fails with:

  Make: Don't know how to make pex-unix.c.  Stop.

This is gdb HEAD on native hppa2.0w-hp-hpux11.11,
using HP Make with a version string of 
"CUP11.11_BL2002_1008_3 PATCH_11.11 PHC0_27755".

Michael C