xhci: refactor static MSI-X function

xhci: refactor static MSI-X function

The current way the xhci driver sets up MSI/MSI-X interrupts is overly
complex and messy. The whole MSI/MSI-X setup can be done in one simple
function.

Start refactoring this by incorporating 'xhci_setup_msix()' into
'xhci_try_enable_msi()'. 'xhci_setup_msix()' is a static function which
is only called by 'xhci_try_enable_msi()'.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20231201150647.1307406-14-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>