Return the IRQ name, alias or number (choose the best for human).

        IRQ line samples:
        1:      44487        341         44         72   IO-APIC   1-edge      i8042
        LOC:   33549868   22394684   32474570   21855077   Local timer interrupts

def __humanname(self, line):
        """Return the IRQ name, alias or number (choose the best for human).

        IRQ line samples:
        1:      44487        341         44         72   IO-APIC   1-edge      i8042
        LOC:   33549868   22394684   32474570   21855077   Local timer interrupts
        """
        splitted_line = line.split()
        irq_line = splitted_line[0].replace(':', '')
        if irq_line.isdigit():
            # If the first column is a digit, use the alias (last column)
            irq_line += '_{}'.format(splitted_line[-1])
        return irq_line