conftools/get-version.sh: Fix unsafe expansions of $hdr
conftools/get-version.sh: Fix unsafe expansions of $hdr

Also, use $() instead of ``. See http://mywiki.wooledge.org/BashFAQ/082.

libexpat/libexpat,libexpat/libexpat,libexpat/libexpat,libexpat/libexpat,libexpat/libexpat,libexpat/libexpat