KVM: selftests: Rename the ASSERT_EQ macro

There is already an ASSERT_EQ macro in the file
tools/testing/selftests/kselftest_harness.h, so currently KVM selftests
can't include test_util.h from the KVM selftests together with that file.
Rename the macro in the KVM selftests to TEST_ASSERT_EQ to avoid the
problem - it is also more similar to the other macros in test_util.h that
way.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Link: https://lore.kernel.org/r/20230712075910.22480-2-thuth@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

KVM: selftests: Add test for race in kvm_recalculate_apic_map()

Keep switching between LAPIC_MODE_X2APIC and LAPIC_MODE_DISABLED during
APIC map construction to hunt for TOCTOU bugs in KVM. KVM's optimized map
recalc makes multiple passes over the list of vCPUs, and the calculations
ignore vCPU's whose APIC is hardware-disabled, i.e. there's a window where
toggling LAPIC_MODE_DISABLED is quite interesting.

Signed-off-by: Michal Luczaj <mhal@rbox.co>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20230602233250.1014316-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>