omapfb/dss: Delete an error message for a failed memory allocation in three functions

[Joe Perches]

On Tue, 2017-11-28 at 08:41 +0100, SF Markus Elfring wrote:
> > > It seems that I got no responses so far for clarification requests
> > > according to the documentation in a direction I hoped for.
> > 
> > That's because you are pretty unresponsive to direction.
> 
> From which places did you get this impression?

How many times have I told you to include the reason for
your patches in
your proposed commit message?  Too often.

For instance, specific to this patch:

Many people do not know that a generic kmalloc does a
dump_stack() on OOM.  That information should be part
of the commit message.

Also removing the printk code reduces overall code size.
The actual size reduction should be described in the
commit message too.