alf_queue_concurrency: minor fix, define U32_MAX if not defined

The define U32_MAX is fairly new it seems (v3.14-rc1~108^2~133), thus
define it ourself if it does not exist, so this works on older kernels.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
qmempool: compile for for older kernels due to in_softirq()

For debugging in_softirq() is used, but on older kernels this was not
getting included appropiately.

Include <linux/hardirq.h> to get in_softirq() defined.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>