An attempt at producing the correct Makefile magic for wrepld_proto.h to be

An attempt at producing the correct Makefile magic for wrepld_proto.h to be
automatically generated on first 'make'.  This wasn't being picked up by the
build farm becouse of the explicit 'make proto'.

The 'make proto' bit isn't somthing our alpha testers know about (its certainly
not clearly documented) and its meant to be automatic.

I hope this works...

Andrew Bartlett
(This used to be commit 3a413ef1eabbb28b589e5238d9c837a8275b54d0)