* random/jitterentropy-base.c (jent_version): Uncomment function.
* random/rndjent.c: Include time.h
(JENT_USES_RDTSC): New.
(JENT_USES_GETTIME): New.
(JENT_USES_READ_REAL_TIME): New.
(jent_get_nstime): Support clock_gettime and AIX specific
function.  Taken from Stephan Müller's code.
(is_rng_available): New.
(_gcry_rndjent_dump_stats): Use that function.
(_gcry_rndjent_poll): Use that fucntion.  Allow an ADD of NULL for an
intialize only mode.
(_gcry_rndjent_get_version): New.