fix(versal_net): evaluate condition for boolean

This corrects the MISRA violation C2012-11.9:
The macro NULL shall be the only permitted form of integer
null pointer constant.
The condition is compared with NULL to get boolean result.

Change-Id: Iff25e69c646337867caad0d992d814c3cd4260cf
Signed-off-by: Maheedhar Bollapalli <maheedharsai.bollapalli@amd.com>
diff --git a/plat/xilinx/versal_net/plat_psci_pm.c b/plat/xilinx/versal_net/plat_psci_pm.c
index fb2005d..7a653d4 100644
--- a/plat/xilinx/versal_net/plat_psci_pm.c
+++ b/plat/xilinx/versal_net/plat_psci_pm.c
@@ -247,7 +247,7 @@
 
 	int32_t pstate = psci_get_pstate_type(power_state);
 
-	assert(req_state);
+	assert(req_state != NULL);
 
 	/* Sanity check the requested state */
 	if (pstate == PSTATE_TYPE_STANDBY) {