KVM: x86 emulator: fix test_cc() build failure on i386

'pushq' doesn't exist on i386.  Replace with 'push', which should work
since the operand is a register.

Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>