camerserver: Remove dependency on libmediandk.

libmediandk brings in many unneeded dependencies which results in
an abnormal increase in vss. AImageReader_getHGBPFromHandle has been
moved to libmediautils.

Test: mm -j64
Test: showmap <pid of cameraserver> vss before change: 50628
Test: showmap <pid of cameraserver> vss after change: 31256

Change-Id: I4de95d08ae514c252a1e01f3b03e0021c821b72a
Signed-off-by: Jayant Chowdhary <jchowdhary@google.com>