Fixes to build get_count for newer Yosys versions

Signed-off-by: Maciej Kurc <mkurc@antmicro.com>
diff --git a/get_count-plugin/get_count.cc b/get_count-plugin/get_count.cc
index 8a4a0ee..1e68973 100644
--- a/get_count-plugin/get_count.cc
+++ b/get_count-plugin/get_count.cc
@@ -21,6 +21,10 @@
 #include "kernel/register.h"
 #include "kernel/rtlil.h"
 
+#ifndef YS_OVERRIDE
+#define YS_OVERRIDE override
+#endif
+
 USING_YOSYS_NAMESPACE
 PRIVATE_NAMESPACE_BEGIN
 
diff --git a/get_count-plugin/tests/Makefile b/get_count-plugin/tests/Makefile
index 487e07e..80cdc79 100644
--- a/get_count-plugin/tests/Makefile
+++ b/get_count-plugin/tests/Makefile
@@ -1,6 +1,6 @@
 TESTS = $(subst /, ,$(wildcard */))
 
-all: $(addsuffix /ok,$(TESTS))
+all: clean $(addsuffix /ok,$(TESTS))
 
 clean:
 	@find . -name "ok" | xargs rm -rf