Fix random.ko module.
- Remove duplicated sources between standard part of the kernel and
  module.  In particular, it caused duplicated lock initialization and
  sysctl registration, both having bad consequences.
- Add missed source files to module.
- Static part of the kernel provides randomdev module, not
  random_adaptors.  Correct dependencies.
- Use cdev modules declaration macros.

Approved by:	secteam (delphij)
Reviewed by:	markm