Move hosts, hosts.equiv, networks, nsswitch.conf, protocols to lib/libc/net/

This uses relative paths to make it more specific to avoid any potential
future problems with .PATH and leverages CONFS.

libc was picked as the destination location for these because of the syscalls
that use these files as the lowest level place they are referenced.

Approved by:	re (gjb), will (mentor)
Differential Revision:	https://reviews.freebsd.org/D17164

etc/Makefile

@@ -16,18 +16,13 @@ BIN1=	\
 	dhclient.conf \
 	disktab \
 	group \
-	hosts \
 	hosts.allow \
-	hosts.equiv \
 	libalias.conf \
 	libmap.conf \
 	login.access \
 	mac.conf \
 	netconfig \
-	networks \
-	nsswitch.conf \
 	phones \
-	protocols \
 	rc.bsdextended \
 	rc.firewall \
 	remote \
@@ -160,10 +155,6 @@ distribution:
 	    ${DESTDIR}/boot/device.hints
 .endif
 .endif
-.if ${MK_NIS} == "no"
-	sed -i "" -e 's/.*_compat:/# &/' -e 's/compat$$/files/' \
-		${DESTDIR}/etc/nsswitch.conf
-.endif
 
 MTREE_CMD?=	mtree
 

lib/libc/net/Makefile.inc

@@ -4,6 +4,7 @@
 # machine-independent net sources
 .PATH: ${LIBC_SRCTOP}/net
 
+CONFS+=	net/hosts net/hosts.equiv net/networks net/nsswitch.conf net/protocols
 SRCS+=	base64.c ether_addr.c eui64.c \
 	gai_strerror.c getaddrinfo.c \
 	gethostbydns.c gethostbyht.c gethostbynis.c gethostnamadr.c \
@@ -123,3 +124,8 @@ SRCS+=	hesiod.c
 MAN+=	hesiod.3
 .endif
 
+.if ${MK_NIS} == "no"
+afterinstallconfig:
+	sed -i "" -e 's/.*_compat:/# &/' -e 's/compat$$/files/' \
+		${DESTDIR}/etc/nsswitch.conf
+.endif