buildroot

dropwatch: bump to master and fix site

The tool was hosted at fedorahosted.org which was shut down in early
2017. According to a private conversation with the upstream maintainer,
the new home for this tool is on infradead.org so far. So the SITE was
adapted accordingly.

Additionally the version was bumped from 1.4 to current master. This
allows to drop one build patch. The other patches were recreated with
Git.

Cc: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Alexander Dahl <post@lespocky.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>