Avoid the use of linker *_SIZE__ macros

The use of end addresses is preferred over the size of sections.
This was done for some AARCH64 files for PIE with commit [1],
and some extra explanations can be found in its commit message.
Align the missing AARCH64 files.

For AARCH32 files, this is required to prepare PIE support introduction.

 [1] f1722b693d36 ("PIE: Use PC relative adrp/adr for symbol reference")

Change-Id: I8f1c06580182b10c680310850f72904e58a54d7d
Signed-off-by: Yann Gautier <yann.gautier@st.com>
diff --git a/bl2u/aarch32/bl2u_entrypoint.S b/bl2u/aarch32/bl2u_entrypoint.S
index 6391f53..e4dd03d 100644
--- a/bl2u/aarch32/bl2u_entrypoint.S
+++ b/bl2u/aarch32/bl2u_entrypoint.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2021, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -79,7 +79,8 @@
 	 * ---------------------------------------------
 	 */
 	ldr	r0, =__BSS_START__
-	ldr	r1, =__BSS_SIZE__
+	ldr	r1, =__BSS_END__
+	sub 	r1, r1, r0
 	bl	zeromem
 
 	/* --------------------------------------------