drm/gma500: Fix (vblank) IRQs not working after suspend/resume

drm/gma500: Fix (vblank) IRQs not working after suspend/resume

Fix gnome-shell (and other page-flip users) hanging after suspend/resume
because of the gma500's IRQs not working.

This fixes 2 problems with the IRQ handling:

1. gma_power_off() calls gma_irq_uninstall() which does a free_irq(), but
   gma_power_on() called gma_irq_preinstall() + gma_irq_postinstall() which
   do not call request_irq. Replace the pre- + post-install calls with
   gma_irq_install() which does prep + request + post.

2. After fixing 1. IRQs still do not work on a Packard Bell Dot SC (Intel
   Atom N2600, cedarview) netbook.

   Cederview uses MSI interrupts and it seems that the BIOS re-configures
   things back to normal APIC based interrupts during S3 suspend. There is
   some MSI PCI-config registers save/restore code which tries to deal with
   this, but on the Packard Bell Dot SC this is not sufficient to restore
   MSI IRQ functionality after a suspend/resume.

   Replace the PCI-config registers save/restore with pci_disable_msi() on
   suspend + pci_enable_msi() on resume. Fixing e.g. gnome-shell hanging.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220906203852.527663-4-hdegoede@redhat.com