tests/functional: remove all class level fields

tests/functional: remove all class level fields

A number of fields are set at the class level on QemuBaseTest, even
though the exact same named field is then set at the object level
later in most cases.

The 'self.logger' initialization in ACPI bits test needs to be removed
since 'self.log' won't exist at that point in the flow. It already
initialized 'self.logger' later in the setUp() method, so the __init__
method was redundant.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-ID: <20250317124300.84266-1-berrange@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>