BL1: Enable pointer authentication support

The size increase after enabling options related to ARMv8.3-PAuth is:

+----------------------------+-------+-------+-------+--------+
|                            |  text |  bss  |  data | rodata |
+----------------------------+-------+-------+-------+--------+
| CTX_INCLUDE_PAUTH_REGS = 1 |  +108 |  +192 |   +0  |   +0   |
|                            |  0.5% |  0.8% |       |        |
+----------------------------+-------+-------+-------+--------+
| ENABLE_PAUTH = 1           |  +748 |  +192 |  +16  |   +0   |
|                            |  3.7% |  0.8% |  7.0% |        |
+----------------------------+-------+-------+-------+--------+

Results calculated with the following build configuration:

    make PLAT=fvp SPD=tspd DEBUG=1 \
    SDEI_SUPPORT=1                 \
    EL3_EXCEPTION_HANDLING=1       \
    TSP_NS_INTR_ASYNC_PREEMPT=1    \
    CTX_INCLUDE_PAUTH_REGS=1       \
    ENABLE_PAUTH=1

Change-Id: I3a7d02feb6a6d212be32a01432b0c7c1a261f567
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/include/bl1/bl1.h b/include/bl1/bl1.h
index 7b5d875..937b8c7 100644
--- a/include/bl1/bl1.h
+++ b/include/bl1/bl1.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -83,6 +83,7 @@
 
 void bl1_print_next_bl_ep_info(const struct entry_point_info *bl_ep_info);
 
+void bl1_setup(void);
 void bl1_main(void);
 void bl1_plat_prepare_exit(entry_point_info_t *ep_info);