Use INSTALL_DATA (mode 0644) to install changelog and man files

--- Makefile.in.orig	2023-12-14 18:14:23 UTC
+++ Makefile.in
@@ -2,6 +2,7 @@ CPP	= @CXX@
 
 DEFS	+= -DVERSION=$(VERSION) @DEFS@
 CPP	= @CXX@
+INSTALL_DATA = install -m 0644
 INSTALL_PROGRAM = install
 
 SRCS	= ncolorstring.cpp nhline.cpp nvline.cpp nscrollview.cpp nselectlist.cpp nview.cpp \
@@ -48,7 +49,7 @@ install: installman
 	$(INSTALL_PROGRAM) -d $(DESTDIR)$(BINDIR)
 	$(INSTALL_PROGRAM) $(PACKAGE_TARNAME) $(DESTDIR)$(BINDIR)
 	$(INSTALL_PROGRAM) -d $(DESTDIR)$(DOCDIR)
-	$(INSTALL_PROGRAM) changelog $(DESTDIR)$(DOCDIR)
+	$(INSTALL_DATA) changelog $(DESTDIR)$(DOCDIR)
 
 createobj:
 	@if ! [ -d "$(ODIR)" ] ; then echo "create $(ODIR)";  mkdir $(ODIR); fi
@@ -56,7 +57,7 @@ installman:
 installman:
 	@echo "install man (boinctui.1) to " $(DESTDIR)@mandir@/man1 " directory"
 	mkdir -p $(DESTDIR)@mandir@/man1
-	install -m 0644 boinctui.1 $(DESTDIR)@mandir@/man1
+	$(INSTALL_DATA) boinctui.1 $(DESTDIR)@mandir@/man1
 
 #srctgz: clean
 #	@if ! [ -d "../$(PACKAGE_TARNAME)-$(VERSION)" ] ; then echo "create symlink ../$(PACKAGE_TARNAME)-$(VERSION)->$(notdir $(CURDIR))";  ln -n -s $(notdir $(CURDIR)) ../$(PACKAGE_TARNAME)-$(VERSION); fi