removed -flatten command option

Signed-off-by: Maciej Kurc <mkurc@antmicro.com>

ql-iob-plugin/tests/Makefile

diff --git a/ql-iob-plugin/tests/Makefile b/ql-iob-plugin/tests/Makefile
index 40145a8..f6ddd6a 100644
--- a/ql-iob-plugin/tests/Makefile
+++ b/ql-iob-plugin/tests/Makefile
@@ -3,5 +3,5 @@
 all: $(TESTS)
 
 generic:
-	yosys -p "plugin -i ../ql-iob.so; read_verilog design.v; synth_quicklogic -flatten; stat; quicklogic_iob design.pcf pinmap.csv; stat; write_blif -attr -param -cname design.eblif"
+	yosys -p "plugin -i ../ql-iob.so; read_verilog design.v; synth_quicklogic ; stat; quicklogic_iob design.pcf pinmap.csv; stat; write_blif -attr -param -cname design.eblif"
 	@echo $@ PASS