sngrep: don't download patch from Github

sngrep: don't download patch from Github

Patches downloaded from Github are not stable, so bring them in the
tree.

For this package, the patch is not replaced 1:1 with what Github was
providing. Indeed, the URL
https://github.com/irontec/sngrep/pull/191/commits/4740f3341a99eaec105dee202a6fa7828212cdf1.patch
no longer exists. This pull request has been merged, so we instead use
the real upstream commits. However, the upstream developer apparently
messed up, and applied the change in two separate commits, which is
why one patch fetched from Github is replaced by this commit by two
patches in package/sngrep/.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>