Write a SysFS attribute/action

    CLI example:
     .. code-block:: bash

        salt '*' sysfs.write devices/system/cpu/cpu0/cpufreq/scaling_governor 'performance'

def write(key, value):
    '''
    Write a SysFS attribute/action

    CLI example:
     .. code-block:: bash

        salt '*' sysfs.write devices/system/cpu/cpu0/cpufreq/scaling_governor 'performance'
    '''
    try:
        key = target(key)
        log.trace('Writing %s to %s', value, key)
        with salt.utils.files.fopen(key, 'w') as twriter:
            twriter.write(
                salt.utils.stringutils.to_str('{0}\n'.format(value))
            )
            return True
    except Exception:
        return False