ARM: dts: omap5-board-common: remove unneded unit names

This patch fixes the following DTC warnings for omap5-igep0050.dtb,
omap5-sbc-t54.dtb and omap5-uevm.dtb:

"connector@0 has a unit name, but no reg property"
"endpoint@0 has a unit name, but no reg property"
"encoder@0 has a unit name, but no reg property"

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>