target-sparc: Split cpu_put_psr into side-effect and no-side-effect parts

target-sparc: Split cpu_put_psr into side-effect and no-side-effect parts

For inbound migration we really want to be able to set the PSR without
having any side effects, but cpu_put_psr() calls cpu_check_irqs() which
might try to deliver CPU interrupts. Split cpu_put_psr() into the
no-side-effect and side-effect parts.

This includes reordering the cpu_check_irqs() to the end of cpu_put_psr(),
because that function may actually end up calling cpu_interrupt(), which
does not seem like a good thing to happen in the middle of updating the PSR.

Suggested-by: Blue Swirl <blauwirbel@gmail.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>