Include dual-chip RD-N1-Edge in coverity makefile

RD-N1-Edge has a dual chip variant which is built by setting
CSS_SGI_CHIP_COUNT to 2. This will increase the coverage of coverity
analysis in plat/arm/board/rdn1edge/rdn1edge_plat.c and
plat/arm/board/rdn1edge/rdn1edge_topology.c files. Since the make
command covers all the files for rdn1edge platform also, this commit
also removes rdn1edge make command to reduce redundancy.

Change-Id: I6e0c83d23bce21834f430923f2718908793b5f67
Signed-off-by: Vijayenthiran Subramaniam <vijayenthiran.subramaniam@arm.com>
diff --git a/script/tf-coverity/tf-cov-make b/script/tf-coverity/tf-cov-make
index d643ab8..5528f8f 100755
--- a/script/tf-coverity/tf-cov-make
+++ b/script/tf-coverity/tf-cov-make
@@ -200,9 +200,9 @@
     CSS_USE_SCMI_SDS_DRIVER=1 all
 
 #
-# System Guidance for Infrastructure platform RD-N1Edge
+# System Guidance for Infrastructure platform RD-N1-Edge-Dual
 #
-make -j DEBUG=1 PLAT=rdn1edge  ${ARM_TBB_OPTIONS} all
+make -j DEBUG=1 PLAT=rdn1edge CSS_SGI_CHIP_COUNT=2 ${ARM_TBB_OPTIONS} all
 
 #
 # System Guidance for Infrastructure platform RD-E1Edge