coverage.sh: comparing amd64 with i386 should only be done with RUN_MA_SAME_TESTS = yes

coverage.sh

@@ -1490,6 +1490,9 @@ $CMD --mode=$defaultmode --variant=apt --architectures=i386 $DEFAULT_DIST /tmp/d
 } | sort | diff -u - tar2.txt
 rm /tmp/debian-chroot.tar
 END
+# this test compares the contents of different architectures, so this might
+# fail if the versions do not match
+if [ "$RUN_MA_SAME_TESTS" = "yes" ]; then
 	if [ "$HOSTARCH" != amd64 ]; then
 		echo "HOSTARCH != amd64 -- Skipping test..." >&2
 		skipped=$((skipped+1))
@@ -1500,6 +1503,10 @@ else
 		echo "HAVE_QEMU != yes -- Skipping test..." >&2
 		skipped=$((skipped+1))
 	fi
+else
+	echo "RUN_MA_SAME_TESTS != yes -- Skipping test..." >&2
+	skipped=$((skipped+1))
+fi
 
 # to test foreign architecture package installation we choose a package which
 #   - is not part of the native installation set