am335x: configs: Use ISW_ENTRY_ADDR to set SPL_TEXT_BASE

The SPL load address changes based on boot type in HS devices,
ISW_ENTRY_ADDR is used to set this address for AM43xx based SoCs
for similar reasons. Add this same logic for AM33xx devices.

Also make the default value for ISW_ENTRY_ADDR correct for GP
devices based on SoC, HS devices already pick the correct
value in their defconfig.

Signed-off-by: Andrew F. Davis <afd@ti.com>
diff --git a/arch/arm/mach-omap2/am33xx/Kconfig b/arch/arm/mach-omap2/am33xx/Kconfig
index 8fd32c2..56c4406 100644
--- a/arch/arm/mach-omap2/am33xx/Kconfig
+++ b/arch/arm/mach-omap2/am33xx/Kconfig
@@ -119,7 +119,8 @@
 	  point address depending on the device type
 	  (secure/non-secure), boot media (xip/non-xip) and
 	  image headers.
-	default 0x402F4000
+	default 0x402F4000 if AM43XX
+	default 0x402F0400 if AM33XX
 
 config PUB_ROM_DATA_SIZE
 	hex "Size in bytes of the L3 SRAM reserved by ROM to store data"