Rework multitail to be futur friendly regarding ncurses

Drop useless post-patch which are not doing anything anymore
Patch the Makefile to link to ncursesw if this is the implementation we do use
or in the futur link to ncurses (and panel) when only this version will be left
in base

sysutils/multitail/Makefile

@@ -18,14 +18,10 @@ USES=		alias gmake ncurses tar:tgz
 PLIST_FILES=	bin/multitail etc/multitail.conf.sample \
 		man/man1/multitail.1.gz
 PORTDOCS=	readme.txt license.txt
+MAKE_ARGS=	NCURSES_IMPL="${NCURSES_IMPL}"
 
 OPTIONS_DEFINE=	DOCS
 
-post-patch:
-	@${REINPLACE_CMD} -e 's,$$(DESTDIR)/etc/multitail.conf,${PREFIX}/etc/multitail.conf,' \
-		-e 's/CC=gcc/CC?=gcc/' \
-		${WRKSRC}/mt.c ${WRKSRC}/Makefile
-
 do-install:
 	${INSTALL_PROGRAM} ${WRKSRC}/multitail ${STAGEDIR}${PREFIX}/bin/
 	${INSTALL_MAN} ${WRKSRC}/multitail.1 ${STAGEDIR}${MANPREFIX}/man/man1

sysutils/multitail/files/patch-Makefile

@@ -0,0 +1,25 @@
+--- Makefile.orig	2019-11-07 12:56:23 UTC
++++ Makefile
+@@ -19,18 +19,12 @@ CPPFLAGS+=-D$(PLATFORM) -DVERSION=\"$(VERSION)\" $(DEB
+ # build dependency files while compile (*.d)
+ CPPFLAGS+= -MMD -MP
+ 
+-
+-ifeq ($(PLATFORM),Darwin)
+-    LDFLAGS+=-lpanel $(NCURSES_LIB) -lutil -lm
++ifeq ($(NCURSES_IMPL),ncursesw)
++LDFLAGS+=-lpanelw -lncursesw -lutil -lm
+ else
+-ifeq ($(UTF8_SUPPORT),yes)
+-    LDFLAGS+=-lpanelw -lncursesw -lutil -lm
+-    CPPFLAGS+=-DUTF8_SUPPORT
+-else
+-    LDFLAGS+=-lpanel -lncurses -lutil -lm
++LDFLAGS+=-lpanel -lncurses -lutil -lm
+ endif
+-endif
+-
++CPPFLAGS+=-DUTF8_SUPPORT
+ 
+ OBJS:=utils.o mt.o error.o my_pty.o term.o scrollback.o help.o mem.o cv.o selbox.o stripstring.o color.o misc.o ui.o exec.o diff.o config.o cmdline.o globals.o history.o clipboard.o
+ DEPENDS:= $(OBJS:%.o=%.d)