12312 fix unused lib dependencies

*** 18,27 ****
--- 18,28 ----
  #
  # CDDL HEADER END
  #
  #
  # Copyright (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved.
+ # Copyright 2020 Joyent, Inc.
  #
  
  LIBRARY =       sn1_brand.a
  VERS =          .1
  COBJS =         sn1_brand.o
*** 65,76 ****
                  -I. -I$(BRAND_SHARED)/brand/sys -I$(UTSBASE)/common/brand/sn1
  CFLAGS +=       $(CCVERBOSE)
  DYNFLAGS +=     $(DYNFLAGS_$(CLASS))
  DYNFLAGS +=     $(BLOCAL) $(ZNOVERSION) -Wl,-e_start
  #DYNFLAGS +=    -R$(NATIVE_DIR)/lib -R$(NATIVE_DIR)/usr/lib
! LDLIBS +=       -lc -lmapmalloc
  
  $(LIBS):= PICS += $(SHAREDOBJS)
  
  .KEEP_STATE:
  
  all: $(LIBS)
--- 66,78 ----
                  -I. -I$(BRAND_SHARED)/brand/sys -I$(UTSBASE)/common/brand/sn1
  CFLAGS +=       $(CCVERBOSE)
  DYNFLAGS +=     $(DYNFLAGS_$(CLASS))
  DYNFLAGS +=     $(BLOCAL) $(ZNOVERSION) -Wl,-e_start
  #DYNFLAGS +=    -R$(NATIVE_DIR)/lib -R$(NATIVE_DIR)/usr/lib
! LDLIBS +=       -lmapmalloc -lc
  
+ ZGUIDANCE =     -zguidance=nounused
  $(LIBS):= PICS += $(SHAREDOBJS)
  
  .KEEP_STATE:
  
  all: $(LIBS)