Fix TSP_STD_FID macro

Enforce valid FID input in TSP_STD_FID and TSP_FAST_FID macros.
Also remove an undefined behavior by using unsigned literals.

Change-Id: Id37e908da861980a4eaa3a70b37a729f416ce272
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>

include/bl32/tsp/tsp.h

@@ -65,22 +65,21 @@
 #define TSP_DIV		0x2003
 #define TSP_HANDLE_SEL1_INTR_AND_RETURN	0x2004
 
+/*
+ * Identify a TSP service from function ID filtering the last 16 bits from the
+ * SMC function ID
+ */
+#define TSP_BARE_FID(fid)	((fid) & 0xffff)
+
 /*
  * Generate function IDs for TSP services to be used in SMC calls, by
  * appropriately setting bit 31 to differentiate standard and fast SMC calls
  */
-#define TSP_STD_FID(fid)	((fid) | 0x72000000 | (0 << 31))
-#define TSP_FAST_FID(fid)	((fid) | 0x72000000 | (1 << 31))
+#define TSP_STD_FID(fid)	((TSP_BARE_FID(fid) | 0x72000000))
+#define TSP_FAST_FID(fid)	((TSP_BARE_FID(fid) | 0x72000000) | (1u << 31))
 
 /* SMC function ID to request a previously preempted std smc */
 #define TSP_FID_RESUME		TSP_STD_FID(0x3000)
-
-/*
- * Identify a TSP service from function ID filtering the last 16 bits from the
- * SMC function ID
- */
-#define TSP_BARE_FID(fid)	((fid) & 0xffff)
-
 /*
  * Total number of function IDs implemented for services offered to NS clients.
  * The function IDs are defined above