OMAP4: OMAPFB: Always set a x_decim and y_decim in overlays

When using the framebuffer API to setup overlay, there's
currently no way to pass a x_decim and y_decim value in
so set some safe non-zero defaults.  Otherwise, when
the overlay is enabled, zero values will cause divide
by zero error in dispc.

Change-Id: Id2cb4bc4cb6be7b57e3ab5fc28fffc57163faecb
Signed-off-by: Mike J. Chen <mjchen@google.com>
Signed-off-by: Ruslan Bilovol <ruslan.bilovol@ti.com>
OMAP4: OMAPFB: Set overlay zorder to 0 if omapfb API used

Since there's no ioctl to set zorder when modifying overlays
using SETUP_PLANE, it's more useful to userland code if
overlay is 0, so they don't have to use sysfs and first
figure out which overlay is being used by omapfb.

Change-Id: I1c2eeecb0b950439e40eec895d6b89c73df2fd7e
Signed-off-by: Mike J. Chen <mjchen@google.com>
Signed-off-by: Ruslan Bilovol <ruslan.bilovol@ti.com>
OMAP4: DSSCOMP: Check user passed arg in ioctl

Prevent stack overflow if user passes in a value
that's too large for num_ovl.

Change-Id: I86a232544f8acc6a08eca00dfdb71db41f355341
Signed-off-by: Mike J. Chen <mjchen@google.com>
Signed-off-by: Ruslan Bilovol <ruslan.bilovol@ti.com>