staging: mt7621-pci: update driver's TODO file

Some of the things included in driver's TODO file have
been properly achieved. Update file accordly.
Signed-off-by: NSergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/mt7621-pci/TODO

 
 - general code review and cleanup
-- can this be converted to not require PCI_DRIVERS_LEGACY ??
-    The irq returned by pcibios_map_irq is a "hwirq" (hardware irq number)
-    and pci_assign_irq() assigns this directly to dev->irq, which
-    expects a "virq" (virtual irq number).  These numbers are different
-    on MIPS.  There is a gross hack to make it work on one
-    specific platform, so it can be tested.
-- Should this be merged with arch/mips/pci/pci-mt7620.c ??
-- ensure device-tree requirements are documented
 
 Cc:  NeilBrown <neil@brown.name>