random: give sysctl_random_min_urandom_seed a more sensible value

commit d0efdf35a6a71d307a250199af6fce122a7c7e11 upstream.

This isn't used by anything or anywhere, but we can't delete it due to
compatibility. So at least give it the correct value of what it's
supposed to be instead of a garbage one.

Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>