forked from Imagelibrary/rtems
The fix to address CID 1399742 (NO_EFFECT) in commit
f8b6359415 introduced a bug since
LEON3_IrqCtrl_EIrq == -1 in case no extended interrupts are supported by
the interrupt controller. Fix this by checking for
LEON3_IrqCtrl_EIrq > 0.
In addition, interrupt number 0 is reserved and should not be used.