Adds shmem command to print amount of shared memory. This is also a
useful indicator of how much IRAM is left, since shared memory will
expand to fill all unused IRAM.
Removes never-implemented wait param to shared_mem_acquire().
BUG=none
TEST=shmem
Change-Id: I798ff644d701dcba52219b70bec99c06a23d03ec
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/29809
Reviewed-by: Bill Richardson <wfrichar@chromium.org>