avocado/replay_kernel.py: make tcg-icount check in run_vm()

avocado/replay_kernel.py: make tcg-icount check in run_vm()

The icount framework relies on TCG availability. If QEMU is built with
--disable-tcg we won't have icount either, and then this test will fail
with the following message in an IBM POWER9 host:

tests/avocado/replay_kernel.py:ReplayKernelNormal.test_ppc64_pseries:
ERROR: ConnectError: Failed to establish session:
(...)
/11-tests_avocado_replay_kernel.py_ReplayKernelNormal.test_ppc64_pseries/replay.bin:
cannot configure icount, TCG support not available

Although this was revealed in a specific ppc64 scenario, the TCG check
is being done in the common code inside run_vm() because all archs need
TCG to have access to icount.

Cc: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20220303153517.168943-6-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>