test-x86-cpuid-compat qtest produces warnings on TCG

[Peter Maydell]

When running under TCG, the 'test-x86-cpuid-compat' qtest produces
warnings. You can see these for instance in the x64-freebsd-13-build
CI job; here's an example:
 https://gitlab.com/qemu-project/qemu/-/jobs/5918818568

24/837 qemu:qtest+qtest-x86_64 / qtest-x86_64/test-x86-cpuid-compat
          OK               7.32s   45 subtests passed
――――――――――――――――――――――――――――――――――――― ✀  ―――――――――――――――――――――――――――――――――――――
stderr:
qemu-system-x86_64: warning: TCG doesn't support requested feature:
CPUID.07H:EBX.intel-pt [bit 25]
qemu-system-x86_64: warning: TCG doesn't support requested feature:
CPUID.07H:EBX.intel-pt [bit 25]
qemu-system-x86_64: warning: TCG doesn't support requested feature:
CPUID.07H:EBX.intel-pt [bit 25]
qemu-system-x86_64: warning: TCG doesn't support requested feature:
CPUID.07H:EBX.intel-pt [bit 25]


Can somebody look at these and work out whether:
 (a) this is a real problem we need to fix
 (b) this is a problem in the test case and it shouldn't be trying to
     test a feature we don't implement
 (c) we should suppress this warning
?

(filed as https://gitlab.com/qemu-project/qemu/-/issues/2096 )

thanks
-- PMM