* random/rndjent.c: New.
* random/rndlinux.c (_gcry_rndlinux_gather_random): Use rndjent.
* random/rndw32.c (_gcry_rndw32_gather_random): Use rndjent.
(slow_gatherer): Fix compiler warning.
* random/Makefile.am (librandom_la_SOURCES): Add rndjent.c
(EXTRA_librandom_la_SOURCES): Add jitterentropy-base.c and
jitterentropy.h.
(rndjent.o, rndjent.lo): New rules.
* configure.ac: New option --disbale-jent-support
(ENABLE_JENT_SUPPORT): New ac-define.