bin/gen-boost-headers: Don't stumble over "boost" in pathname

...like

  workdir/UnpackedTarball/liborcus/m4/boost.m4:#include <boost/version.hpp>

which would then be mis-parsed by

  grep -o '\bboost.*\.\(h\|hpp\|ipp\)'

to a HEADER of

  boost.m4:#include <boost/version.hpp

instead of just

  boost/version.hpp

(-h is a non-standard GNU grep extension, but so is the already used -r.  An
alternative fix would be to replace the later grep -o with something like

  grep -o '\bboost[^#]*\.\(h\|hpp\|ipp\)'

instead.)

Change-Id: I0b41ed520b2fed70e8982abc0e84a34804c02549

bin/gen-boost-headers

@@ -21,12 +21,12 @@ mkdir ${GENDIR}
 # note: clucene contains a copy of half of boost, so ignore it too
 # note: firebird contains a copy of half of boost, so ignore it too
 
-cat <(cd ${SRCDIR} && git grep '^# *include') \
+cat <(cd ${SRCDIR} && git grep -h '^# *include') \
     <(find ${WORKDIR}/UnpackedTarball/ -mindepth 1 -maxdepth 1 -type d \
          | grep -v boost \
          | grep -v clucene \
          | grep -v firebird \
-         | xargs grep -r '^# *include') \
+         | xargs grep -hr '^# *include') \
  | grep -o '\bboost.*\.\(h\|hpp\|ipp\)' \
  | sort | uniq \
  | while read -r HEADER; do