buildroot

netsniff-ng: bump to version 0.6.3

Drop upstream patch.

Add two more patches to deal with musl build issues.

Cc: Joris Lijssens <joris.lijssens@gmail.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>