New upstream at github. Update homepage link and download site.
Drop the custom extract command; we now get the source tree from github.
Drop patch #2; the code detects rpc support.
Add optional dependency on libtirpc.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>