JAVA: Don't cast returns from malloc()

JAVA: Don't cast returns from malloc()

malloc() returns a (void *) on all of our current platforms. So,
don't bother casting the return value before assigning it - it's
unecessary noise.

Change-Id: I534d424da13e03d3c0f0de3dddf1dd19088d1659
Reviewed-on: http://gerrit.openafs.org/7458
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>