powerpc/boot: Don't change link address for OF-based platforms

Commit c55aef0e5b ("powerpc/boot: Change the load address for the
wrapper to fit the kernel") adjusts the wrapper address unnecessarily
for platforms that use arch/powerpc/boot/of.c, since the code there
allocates space for the kernel wherever it can find it and doesn't
necessarily load the kernel at address 0.  Changing the link address
is actually harmful since it can cause the zImage to overlap with
Open Firmware and thus fail to boot.

To fix this, we set make_space to n for all of the platforms that
use of.o.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/boot/wrapper

@@ -150,18 +150,22 @@ case "$platform" in
 pseries)
     platformo="$object/of.o $object/epapr.o"
     link_address='0x4000000'
+    make_space=n
     ;;
 maple)
     platformo="$object/of.o $object/epapr.o"
     link_address='0x400000'
+    make_space=n
     ;;
 pmac|chrp)
     platformo="$object/of.o $object/epapr.o"
+    make_space=n
     ;;
 coff)
     platformo="$object/crt0.o $object/of.o $object/epapr.o"
     lds=$object/zImage.coff.lds
     link_address='0x500000'
+    make_space=n
     pie=
     ;;
 miboot|uboot*)