Revert "build-xenserver-core: makemake.py is now called by the Makefile"

This reverts commit 927abc0039bb6f50f6d3f23d37ca5278b4b764a0.

Signed-off-by: Euan Harris <euan.harris@citrix.com>
Merge pull request #60 from euanh/master

Revert "build-xenserver-core: makemake.py is now called by the Makefile"