Fix dimensions of psci_req_local_pwr_states

Wrong array size cause compilation error when using GCC 7.2:

lib/psci/psci_common.c: In function ‘psci_do_state_coordination’:
lib/psci/psci_common.c:220:27: error: array subscript is above array bounds [-Werror=array-bounds]
psci_req_local_pwr_states[pwrlvl - 1][cpu_idx] = req_pwr_state;

Change-Id: I5dc189e9624a3773e6f10d56d949d66c18c98206
Signed-off-by: Bernhard Rosenkränzer <bero@lindev.ch>
Reviewed-on: http://vgitil04.il.marvell.com:8080/49631
Tested-by: iSoC Platform CI <ykjenk@marvell.com>
Reviewed-by: Nadav Haklai <nadavh@marvell.com>
Reviewed-by: Kostya Porotchkin <kostap@marvell.com>

lib/psci/psci_common.c

@@ -62,7 +62,7 @@ const spd_pm_ops_t *psci_spd_pm;
  * the cache thrashing can be avoided.
  */
 static plat_local_state_t
-	psci_req_local_pwr_states[PLAT_MAX_PWR_LVL][PLATFORM_CORE_COUNT];
+	psci_req_local_pwr_states[PLAT_MAX_PWR_LVL+1][PLATFORM_CORE_COUNT];
 
 
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