feat(intel): add build config and variant for N5X

Add build config and variant for Intel N5X platforms.

Signed-off-by: Sieu Mun Tang <sieu.mun.tang@intel.com>
Change-Id: I44c7d8f50244e79bb3f5773157fbef0f892a2c85
diff --git a/script/tf-coverity/tf-cov-make b/script/tf-coverity/tf-cov-make
index 02b3f07..577c160 100755
--- a/script/tf-coverity/tf-cov-make
+++ b/script/tf-coverity/tf-cov-make
@@ -437,6 +437,7 @@
 # Platforms from Intel
 make PLAT=stratix10 $(common_flags) all
 make PLAT=agilex $(common_flags) all
+make PLAT=n5x $(common_flags) all
 
 # Platforms from Broadcom
 clean_build PLAT=stingray $(common_flags) BOARD_CFG=bcm958742t \