PCI/MSI: Check MSI_FLAG_PCI_MSI_MASK_PARENT in cond_[startup|shutdown]_parent()

For MSI controllers which only support MSI_FLAG_PCI_MSI_MASK_PARENT, the
newly added callback irq_startup() and irq_shutdown() for
pci_msi[x]_template will not unmask or mask the interrupt when startup()
resp.  shutdown() is invoked. This prevents the interrupt from being
enabled resp. disabled.

Invoke irq_[un]mask_parent() in cond_[startup|shutdown]_parent(), when the
interrupt has the MSI_FLAG_PCI_MSI_MASK_PARENT flag set.

Fixes: 54f45a30 ("PCI/MSI: Add startup/shutdown for per device domains")
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Reported-by: Nathan Chancellor <nathan@kernel.org>
Reported-by: Wei Fang <wei.fang@nxp.com>
Signed-off-by: Inochi Amaoto <inochiama@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Wei Fang <wei.fang@nxp.com>
Tested-by: Chen Wang <unicorn_wang@outlook.com> # Pioneerbox/SG2042
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/all/20250827230943.17829-1-inochiama@gmail.com
Closes: https://lore.kernel.org/regressions/aK4O7Hl8NCVEMznB@monster/
Closes: https://lore.kernel.org/regressions/20250826220959.GA4119563@ax162/
Closes: https://lore.kernel.org/all/20250827093911.1218640-1-wei.fang@nxp.com/