Revert "msm: vidc: Handle encoder input in true dynamic mode"

This reverts commit 1681bd42 ("msm: vidc: Handle encoder
input in true dynamic mode") Keep iova mappings of encoder
input buffers as we move towards a handle based mapping and
encoder input buffers once allocated are maintained through-
out the session.

CRs-Fixed: 1026885
Change-Id: Ib6df539c5e04ba4eefed59355fd13191f85492d8
Signed-off-by: Srinu Gorle <sgorle@codeaurora.org>
Signed-off-by: Abdulla Anam <abdullahanam@codeaurora.org>