random: optimize the entropy_store structure
random: optimize the entropy_store structure

Use smaller types to slightly shrink the size of the entropy store
structure.

Signed-off-by: "Theodore Ts'o" <4ed386e0495d3e109932df055831d9ec2f824927@mit.edu>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs