net: qrtr: Respond to HELLO message

Lost in the translation from the user space implementation was the
detail that HELLO mesages must be exchanged between each node pair.  As
such the incoming HELLO must be replied to.

Similar to the previous implementation no effort is made to prevent two
Linux boxes from continuously sending HELLO messages back and forth,
this is left to a follow up patch.

say_hello() is moved, to facilitate the new call site.

Change-Id: I1b1d66c6a24edf5758d05b76fd527b7d2a35c5da
Fixes: 0c2204a4ad71 ("net: qrtr: Migrate nameservice to kernel from userspace")
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Git-commit: a1dc1d6a05a730b62b45828975a088db577d3139
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Signed-off-by: Chris Lew <clew@codeaurora.org>