This adds boot Linux tests for x86_64, aarch64, ppc64, and s390x
targets which, unlike others, enable the KVM acceleration. Likewise
it was added test cases for tcg.

It is introduced an infraestructure on avocado_qemu framework
so that:
a) simply tagging the test with `accel:kvm` (or `accel:tcg`) will
automatically set the corresponding '-accel' on the launched
QEMU;
b) test is canceled if the accelerator is not enabled on the QEMU
binary or not available in the host.

The acceptance builder on Travis was changed too in order to make
the test run.

Changes v2 -> v3:
- Uses '-accel kvm' rather than '-enable-kvm' when automatically setting
  the accelerator [thuth]
- Added patch 04 which enable the KVM acceptance tests to run on
  Travis [thuth]
v2: [PATCH v2 0/3] Acceptance tests: boot Linux with KVM test
- https://www.mail-archive.com/qemu-devel@nongnu.org/msg666238.html
v1: [PATCH 0/3] Acceptance tests: boot Linux with KVM test
- https://www.mail-archive.com/qemu-devel@nongnu.org/msg627498.html

Tree:
- Git: https://github.com/wainersm/qemu
- Branch: acceptance_kvm_test-v3

CI:
- Travis (PASS): https://travis-ci.org/wainersm/qemu/builds/640172969

Wainer dos Santos Moschetta (4):
  tests/acceptance: avocado_qemu: Introduce the 'accel' test parameter
  tests/acceptance: boot_linux_console: Add boot Linux with kvm tests
  tests/acceptance: avocado_qemu: Refactor the handler of 'machine'
    parameter
  travis.yml: Enable acceptance KVM tests

 .travis.yml                               |  7 +-
 docs/devel/testing.rst                    | 16 +++++
 tests/acceptance/avocado_qemu/__init__.py | 27 ++++++-
 tests/acceptance/boot_linux_console.py    | 88 +++++++++++++++++------
 4 files changed, 115 insertions(+), 23 deletions(-)

-- 
2.23.0