ARM: 7549/1: HYP: fix boot on some ARM1136 cores

It appears that performing a "movs pc, lr" to force the kernel into
SVC mode on the OMAP2420 (ARM1136) prevents the platform from booting
correctly (change introduced in 80c59daf [ARM: virt: allow the kernel
to be entered in HYP mode]).

While the reason it fails is not understood yet (the same code runs
fine on the OMAP2430, ARM1136 as well), partially revert that change
for platforms that do not enter in HYP mode, preserving the new
feature and restoring a working kernel on the OMAP2420.

Reported-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>