Makefile: avoid GNU install options

The install-tools target installs the sunxi-fel man page with
"install -D -m0644 -t", which is supported by GNU install but not by
BSD install. This breaks "make install" on systems such as macOS.

Create the man page directory explicitly and install the file to its
full destination path instead. This matches the existing directory
creation used for the binary install path and works with both GNU and
BSD install.

Signed-off-by: James Hilliard <james.hilliard1@gmail.com>

Author: jameshilliard

Makefile

@@ -96,7 +96,8 @@ install-tools: $(TOOLS)
 	@set -ex ; for l in $(FEXC_LINKS) ; do \
 		ln -nfs sunxi-fexc $(DESTDIR)$(BINDIR)/$$l ; \
 	done
-	install -D -m0644 -t $(DESTDIR)$(MANDIR) sunxi-fel.1
+	install -d $(DESTDIR)$(MANDIR)
+	install -m0644 sunxi-fel.1 $(DESTDIR)$(MANDIR)/sunxi-fel.1
 
 install-target-tools: $(TARGET_TOOLS)
 	install -d $(DESTDIR)$(BINDIR)