Use install instead of cp for install purposes.

The install utility will set the proper permissions for the file
at hand while cp just sets the permissions at the destination
it gets from the original file - which might be totally wrong
depending on the users' umask.

Signed-off-by: Henner Zeller <h.zeller@acm.org>

Makefile_plugin.common

diff --git a/Makefile_plugin.common b/Makefile_plugin.common
index 4289bd6..06f2c61 100644
--- a/Makefile_plugin.common
+++ b/Makefile_plugin.common
@@ -48,8 +48,7 @@
 	$(CXX) $(CXXFLAGS) $(LDFLAGS) -shared -o $@ $^ $(LDLIBS)
 
 install_plugin: $(NAME).so
-	mkdir -p $(PLUGINS_DIR)
-	cp $< $(PLUGINS_DIR)/$<
+	install -D $< $(PLUGINS_DIR)/$<
 
 test:
 	$(MAKE) -C tests all

xdc-plugin/Makefile

diff --git a/xdc-plugin/Makefile b/xdc-plugin/Makefile
index bd454a1..0ca7ba3 100644
--- a/xdc-plugin/Makefile
+++ b/xdc-plugin/Makefile
@@ -4,7 +4,6 @@
 VERILOG_MODULES = BANK.v
 
 install_modules: $(VERILOG_MODULES)
-	mkdir -p $(PLUGINS_DIR)/fasm_extra_modules/
-	cp $< $(PLUGINS_DIR)/fasm_extra_modules/$<
+	install -D $< $(PLUGINS_DIR)/fasm_extra_modules/$<
 
 install: install_modules