Clarify platform porting interface to TSP

* Move TSP platform porting functions to new file:
  include/bl32/tsp/platform_tsp.h.

* Create new TSP_IRQ_SEC_PHY_TIMER definition for use by the generic
  TSP interrupt handling code, instead of depending on the FVP
  specific definition IRQ_SEC_PHY_TIMER.

* Rename TSP platform porting functions from bl32_* to tsp_*, and
  definitions from BL32_* to TSP_*.

* Update generic TSP code to use new platform porting function names
  and definitions.

* Update FVP port accordingly and move all TSP source files to:
  plat/fvp/tsp/.

* Update porting guide with above changes.

Note: THIS CHANGE REQUIRES ALL PLATFORM PORTS OF THE TSP TO
      BE UPDATED

Fixes ARM-software/tf-issues#167

Change-Id: Ic0ff8caf72aebb378d378193d2f017599fc6b78f
diff --git a/plat/fvp/include/platform_def.h b/plat/fvp/include/platform_def.h
index c87ba54..32f070f 100644
--- a/plat/fvp/include/platform_def.h
+++ b/plat/fvp/include/platform_def.h
@@ -32,7 +32,7 @@
 #define __PLATFORM_DEF_H__
 
 #include <arch.h>
-#include <../fvp_def.h>
+#include "../fvp_def.h"
 
 
 /*******************************************************************************
@@ -131,8 +131,8 @@
 #if FVP_TSP_RAM_LOCATION_ID == FVP_IN_TRUSTED_SRAM
 # define TSP_SEC_MEM_BASE		FVP_TRUSTED_SRAM_BASE
 # define TSP_SEC_MEM_SIZE		FVP_TRUSTED_SRAM_SIZE
+# define TSP_PROGBITS_LIMIT		BL2_BASE
 # define BL32_BASE			FVP_TRUSTED_SRAM_BASE
-# define BL32_PROGBITS_LIMIT		BL2_BASE
 # define BL32_LIMIT			BL31_BASE
 #elif FVP_TSP_RAM_LOCATION_ID == FVP_IN_TRUSTED_DRAM
 # define TSP_SEC_MEM_BASE		FVP_TRUSTED_DRAM_BASE
@@ -144,6 +144,11 @@
 # error "Unsupported FVP_TSP_RAM_LOCATION_ID value"
 #endif
 
+/*
+ * ID of the secure physical generic timer interrupt used by the TSP.
+ */
+#define TSP_IRQ_SEC_PHY_TIMER		IRQ_SEC_PHY_TIMER
+
 /*******************************************************************************
  * Platform specific page table and MMU setup constants
  ******************************************************************************/
@@ -152,11 +157,6 @@
 #define MAX_MMAP_REGIONS		16
 
 /*******************************************************************************
- * ID of the secure physical generic timer interrupt.
- ******************************************************************************/
-#define IRQ_SEC_PHY_TIMER		29
-
-/*******************************************************************************
  * Declarations and constants to access the mailboxes safely. Each mailbox is
  * aligned on the biggest cache line size in the platform. This is known only
  * to the platform as it might have a combination of integrated and external