staging: etnaviv: clean up printk()s etc

Report messages against the component device rather than the subsystem
device, so that the component responsible for the message is identified
rather than having to be separately formatted in the string.  This
ensures that many of the debug messages are properly attributed to their
appropriate component, which is especially important when we have
multiple GPU cores in a SoC.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>