Get rid of some GNU make extensions so users can build with

the make that comes with *BSD and other systems now.

Change-Id: Ib2eee8d37e7029202675bac35839b1c0d5fc5131
Reviewed-on: https://code.wireshark.org/review/6320
Reviewed-by: Stephen Fisher <sfisher@sdf.org>

epan/dissectors/Makefile.am

@@ -54,7 +54,7 @@ EXTRA_DIST = \
 	x11-fields
 
 packet-ncp2222.c : $(top_srcdir)/tools/ncp2222.py
-	$(PYTHON) $< -o $@
+	$(PYTHON) $(top_srcdir)/tools/ncp2222.py -o $@
 
 # Target to rebuild the X11 dissector header files.
 # See README.X11 before using this--it requires the xcb and mesa source.

packaging/macosx/Makefile.am

@@ -92,7 +92,7 @@ EXTRA_DIST = \
 
 
 COPYING.txt: ../../COPYING
-	cp $< $@
+	cp ../../COPYING $@
 
 all: COPYING.txt