arm: armada-xp: Fix SPL for AXP by using save_boot_params_ret

Patch e11c6c27 (arm: Allow lr to be saved by board code) introduced
a different method to return from save_boot_params(). The SPL support
for AXP has been pulled and changing to this new method is now
required for SPL to work correctly.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Luka Perkov <luka.perkov@sartura.hr>

arch/arm/cpu/armv7/armada-xp/lowlevel_spl.S

@@ -6,7 +6,7 @@
 #include <linux/linkage.h>
 
 ENTRY(save_boot_params)
-	bx	lr
+	b	save_boot_params_ret
 ENDPROC(save_boot_params)
 
 /*