#137 [rng-tools] outdated defaults

[Disconnect]

While https://www.kernel.org/doc/Documentation/hw_random.txt shows /dev/hw_random as the default name, https://git.kernel.org/cgit/linux/kernel/git/bwh/linux-3.2.y.git/tree/drivers/char/hw_random/core.c#n180 uses /dev/hwrng. (It looks like that changed in 2009: https://git.kernel.org/cgit/linux/kernel/git/bwh/linux-3.2.y.git/commit/drivers/char/hw_random/core.c?id=d405640539555b601e52f7d18f1f0b1345d18bf5 )

The rng-tools default should probably match the upstream.