PCI: altera: Remove unused num_of_vectors variable

The local variable "num_of_vectors" was unused, so remove it.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Ley Foon Tan <lftan@altera.com>