KVM test: Replace some kvm_subprocess usage with utils.system

The preprocessing command and qemu-img command are
currently ran using kvm_subprocess. However, those
commands have no need to use that API, considering
that we don't need to interact with those commands
or make them persist between tests.

Using utils.system() instead of kvm_subprocess
speeds up the command execution, and simplifies
the code a bit.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>


git-svn-id: http://test.kernel.org/svn/autotest/trunk@4212 592f7852-d20e-0410-864c-8624ca9c26a4
2 files changed