arm: relocate_code(): Use __image_copy_end for end of relocation

Use __image_copy_end instead of __bss_start for the end of the image to
relocate. This is the same as commit 033ca72, but applied to all ARM start.S.

This is a more appropriate symbol naming for an image copy & relocate feature,
and this also saves a useless copy of data put between __image_copy_end and
__bss_start in linker scripts (e.g. relocation information, or MMU
initialization tables used only before jumping to the relocated image).

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
diff --git a/board/actux3/u-boot.lds b/board/actux3/u-boot.lds
index fc48cf0..168fe17 100644
--- a/board/actux3/u-boot.lds
+++ b/board/actux3/u-boot.lds
@@ -61,6 +61,9 @@
 	}
 
 	. = ALIGN (4);
+
+	__image_copy_end = .;
+
 	.rel.dyn : {
 		__rel_dyn_start = .;
 		*(.rel*)