Move contrib/zlib to sys/contrib/zlib so that we can use it in kernel.

This is a prerequisite of unifying kernel zlib instances.

Submitted by:	Yoshihiro Ota <ota at j.email.ne.jp>
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D20191

lib/libz/FREEBSD-upgrade

@@ -8,7 +8,7 @@ benefit other consumers.
 To Update:
   1) Unpack vendor sources into a clean directory.
   2) Import onto the vendor area.
-  3) Merge the vendor tree to contrib/zlib, which contains a stripped down
+  3) Merge the vendor tree to sys/contrib/zlib, which contains a stripped down
      version of upstream source, resolve any conflicts.
   4) Double check zconf.h, zlib.pc, and Symbol.map to make sure that we
      have the required changes.  Test universe and commit them.

lib/libz/Makefile

@@ -9,7 +9,7 @@ SHLIB_MAJOR=	6
 MAN=		zlib.3 zopen.3
 MLINKS+=	zopen.3 zdopen.3
 
-ZLIBSRC=	${SRCTOP}/contrib/zlib
+ZLIBSRC=	${SRCTOP}/sys/contrib/zlib
 
 .PATH:		${ZLIBSRC}
 

stand/libsa/Makefile

@@ -99,8 +99,8 @@ CFLAGS+= -DBZ_NO_STDIO -DBZ_NO_COMPRESS
 SRCS+=bzlib.c crctable.c decompress.c huffman.c randtable.c
 
 # decompression functionality from zlib
-.PATH: ${SRCTOP}/contrib/zlib
-CFLAGS+=-DHAVE_MEMCPY -I${SRCTOP}/contrib/zlib
+.PATH: ${SRCTOP}/sys/contrib/zlib
+CFLAGS+=-DHAVE_MEMCPY -I${SRCTOP}/sys/contrib/zlib
 SRCS+=	adler32.c crc32.c
 SRCS+=	infback.c inffast.c inflate.c inftrees.c zutil.c
 

usr.bin/minigzip/Makefile

@@ -1,6 +1,6 @@
 # $FreeBSD$
 
-SRCDIR=	${SRCTOP}/contrib/zlib/test
+SRCDIR=	${SRCTOP}/sys/contrib/zlib/test
 .PATH:	${SRCDIR}
 
 PROG=	minigzip