arm: mach-omap2: Enable Kconfig support for K2 HS devices

Like the OMAP54xx, AM43xx, & AM33xx family SoCs, the keystone family
of SoCs also have high security enabled models. Allow K2E devices to
be built with HS Device Type Support.

Signed-off-by: Vitaly Andrianov <vitalya@ti.com>
Signed-off-by: Madan Srinivas <madans@ti.com>
Signed-off-by: Andrew F. Davis <afd@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Lokesh Vutla <lokeshvutla@ti.com>

arch/arm/mach-omap2/Kconfig

 config TI_SECURE_DEVICE
 	bool "HS Device Type Support"
-	depends on OMAP54XX || AM43XX || AM33XX
+	depends on OMAP54XX || AM43XX || AM33XX || ARCH_KEYSTONE
 	help
 	  If a high secure (HS) device type is being used, this config
 	  must be set. This option impacts various aspects of the