8411 Build should warn when linking against libraries outside proto area

*** 18,27 ****
--- 18,28 ----
  #
  # CDDL HEADER END
  #
  # Copyright (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved.
  # Copyright (c) 2016 by Delphix. All rights reserved.
+ # Copyright 2017 RackTop Systems.
  #
  LIBRARY =       libshare.a
  VERS =          .1
  NFSLIB_DIR =    $(SRC)/cmd/fs.d/nfs/lib
  
*** 39,48 ****
--- 40,52 ----
  
  LIBS =          $(DYNLIB) $(LINTLIB)
  LDLIBS +=       -lc -lnsl -lscf -lzfs -luuid -lxml2 -lnvpair
  $(LINTLIB) :=   SRCS = $(SRCDIR)/$(LINTSRC)
  
+ # Allow libxml2 to be taken from outside the proto area.
+ $(ADJUNCT_PROTO_NOT_SET)DYNFLAGS += $(ZASSERTDEFLIB)=libxml2.so
+ 
  #add nfs/lib directory as part of the include path
  CFLAGS +=       $(CCVERBOSE)
  C99MODE +=      $(C99_ENABLE)
  CERRWARN +=     -_gcc=-Wno-parentheses
  CERRWARN +=     -_gcc=-Wno-uninitialized