All nodes inhert "interrupt-parent" property from root
node. Removed the aforementioned property from usbhsohci,
usbhsehci, ssi_port1, ssi_port2 nodes to avoid duplication.
Signed-off-by: Karthik Tummala <karthik@techveda.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>