Add skeleton Yosys-Libero igloo2 example project

Signed-off-by: Clifford Wolf <clifford@clifford.at>

examples/igloo2/libero.tcl

@@ -0,0 +1,14 @@
+# Run with "libero SCRIPT:libero.tcl"
+
+new_project \
+    -name top \
+    -location work \
+    -family IGLOO2 \
+    -die PA4MGL500 \
+    -package tq144 \
+    -speed -1 \
+    -hdl VERILOG
+
+import_files -edif {example.edn}
+run_tool –name {COMPILE}
+run_tool –name {PLACEROUTEN}