The attached patch does the following:

The attached patch does the following:

- introduces two basic tests for the virtual TPM (skipped on hardware
where a TPM is not available or vtpm manager has not been started
manually before)
- adapts the Makefiles to make the test cases available
- splits up the hotplug files into two files where the vtpm-common.sh
can be sourced by 'other' scripts as well
- uses echo "$var" to return variables from functions
- gets rid of the 'set +e" work-around
- introduces a script (vtpm-delete) to delete entries from the virtual
TPM directory in /etc/xen/vtpm.db

The xm-tests will skip over the 2nd test on most systems and the patch
has otherwise no effect on existing tests.

Signed-off-by: Stefan Berger <stefanb@us.ibm.com>