IRQ assignments in M1535

Master PIC
----------
IRQ 0 (IR0)    
IRQ 1 (IR1)    (Kbd?)
IRQ 2 (IR2)    Slave PIC
IRQ 3 (IR3)
IRQ 4 (IR4)    UART1
IRQ 5 (IR5)
IRQ 6 (IR6)    FDC
IRQ 7 (IR7)    

Slave PIC
---------
IRQ 8 (IR0)
IRQ 9 (IR1)    UART2
IRQ 10 (IR2)
IRQ 11 (IR3)
IRQ 12 (IR4)
IRQ 13 (IR5)
IRQ 14 (IR6)
IRQ 15 (IR7)
