simplify fdt libs selection

Signed-off-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Makefile.target

@@ -514,9 +514,7 @@ CPPFLAGS += -DHAS_AUDIO -DHAS_AUDIO_CHOICE
 endif
 
 obj-ppc-$(CONFIG_FDT) += device_tree.o
-ifdef FDT_LIBS
 LIBS+= $(FDT_LIBS)
-endif
 
 obj-mips-y = mips_r4k.o mips_jazz.o mips_malta.o mips_mipssim.o
 obj-mips-y += mips_timer.o mips_int.o dma.o vga.o serial.o i8254.o i8259.o rc4030.o
@@ -542,9 +540,7 @@ obj-microblaze-y += xilinx_ethlite.o
 obj-microblaze-y += pflash_cfi02.o
 
 obj-microblaze-$(CONFIG_FDT) += device_tree.o
-ifdef FDT_LIBS
 LIBS+= $(FDT_LIBS)
-endif
 
 # Boards
 obj-cris-y = cris_pic_cpu.o etraxfs.o axis_dev88.o

configure

@@ -1257,11 +1257,12 @@ fi
 ##########################################
 # fdt probe
 if test "$fdt" = "yes" ; then
-    fdt=no
-    cat > $TMPC << EOF
+  fdt=no
+  fdt_libs="-lfdt"
+  cat > $TMPC << EOF
 int main(void) { return 0; }
 EOF
-  if $cc $ARCH_CFLAGS -o $TMPE ${OS_CFLAGS} $TMPC -lfdt 2> /dev/null > /dev/null ; then
+  if $cc $ARCH_CFLAGS -o $TMPE ${OS_CFLAGS} $TMPC $fdt_libs 2> /dev/null > /dev/null ; then
     fdt=yes
   fi
 fi
@@ -1711,7 +1712,7 @@ fi
 if test "$fdt" = "yes" ; then
   echo "CONFIG_FDT=y" >> $config_host_mak
   echo "#define CONFIG_FDT 1" >> $config_host_h
-  echo "FDT_LIBS=-lfdt" >> $config_host_mak
+  echo "FDT_LIBS=$fdt_libs" >> $config_host_mak
 fi
 
 # XXX: suppress that