tests/tcg: correct target CPU for sparc32

tests/tcg: correct target CPU for sparc32

We do not want v8plus for pure sparc32, as the difference with the V8 ABI
are only meaningful on 64-bit CPUs suh as ultrasparc; supersparc is the
best CPU to use for 32-bit.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220517092616.1272238-7-pbonzini@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220527153603.887929-18-alex.bennee@linaro.org>