arm: start.S: Fix _TEXT_BASE for SPL

_TEXT_BASE must be set to CONFIG_SPL_TEXT_BASE for generic SPL, and to
CONFIG_SYS_TEXT_BASE for non-SPL builds.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Reviewed-by: Tom Rini <trini@ti.com>
diff --git a/arch/arm/cpu/ixp/start.S b/arch/arm/cpu/ixp/start.S
index b725964..8f4fa7b 100644
--- a/arch/arm/cpu/ixp/start.S
+++ b/arch/arm/cpu/ixp/start.S
@@ -98,7 +98,11 @@
 
 .globl _TEXT_BASE
 _TEXT_BASE:
+#if defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_TEXT_BASE)
+	.word	CONFIG_SPL_TEXT_BASE
+#else
 	.word	CONFIG_SYS_TEXT_BASE
+#endif
 
 /*
  * These are defined in the board-specific linker script.