tests/tcg: add compiler test variables when using containers

tests/tcg: add compiler test variables when using containers

Even for container-based cross compilation use $(CROSS_CC_HAS_*) variables.
This makes the TCG test makefiles oblivious of whether the compiler is
invoked through a container or not.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220401141326.1244422-10-pbonzini@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220419091020.3008144-13-alex.bennee@linaro.org>