Add build config for Morello Platform

Also updated the coverity makefile with Morello build command

Signed-off-by: Chandni Cherukuri <chandni.cherukuri@arm.com>
Change-Id: Idf2374de8cda649ddc5f4fff4d1eb39d6904583d
diff --git a/script/tf-coverity/tf-cov-make b/script/tf-coverity/tf-cov-make
index 26c38a0..fa3a68e 100755
--- a/script/tf-coverity/tf-cov-make
+++ b/script/tf-coverity/tf-cov-make
@@ -302,6 +302,11 @@
 #
 make $(common_flags) PLAT=tc0 ${ARM_TBB_OPTIONS} all
 
+#
+# Morello platform
+#
+make $(common_flags) PLAT=morello all
+
 # Partners' platforms.
 # Enable as many features as possible.
 # We don't need to clean between each build here because we only do one build