main/rng-tools: upgrade to 6.11

Take over maintainership.
Remove unneeded patches.
DARN source no longer requires libgcrypt.
Overhaul conf.d file to give more flexibility in selecting features.
Add jitterentropy-library dependancy - jitter source now built into rngd.
Add patch to fix jitter compile warning.
Disable RTLSDR in rngd to remove various dependancies.
Add rng-tools-extra sub-package with more entropy sources compiled-in.