TSP: 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 |   +40 |   +0  |   +0  |   +0   |
|                            |  0.4% |       |       |        |
+----------------------------+-------+-------+-------+--------+
| ENABLE_PAUTH = 1           |  +352 |    +0 |  +16  |   +0   |
|                            |  3.1% |       | 15.8% |        |
+----------------------------+-------+-------+-------+--------+

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: I6cc1fe0b2345c547dcef66f98758c4eb55fe5ee4
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/bl32/tsp/tsp_main.c b/bl32/tsp/tsp_main.c
index 407ed47..30bf6ff 100644
--- a/bl32/tsp/tsp_main.c
+++ b/bl32/tsp/tsp_main.c
@@ -72,6 +72,26 @@
 }
 
 /*******************************************************************************
+ * Setup function for TSP.
+ ******************************************************************************/
+void tsp_setup(void)
+{
+	/* Perform early platform-specific setup */
+	tsp_early_platform_setup();
+
+	/*
+	 * Update pointer authentication key before the MMU is enabled. It is
+	 * saved in the rodata section, that can be writen before enabling the
+	 * MMU. This function must be called after the console is initialized
+	 * in the early platform setup.
+	 */
+	bl_handle_pauth();
+
+	/* Perform late platform-specific setup */
+	tsp_plat_arch_setup();
+}
+
+/*******************************************************************************
  * TSP main entry point where it gets the opportunity to initialize its secure
  * state/applications. Once the state is initialized, it must return to the
  * SPD with a pointer to the 'tsp_vector_table' jump table.