rb532: image: fix broken ifneq statement

Fixes the following build error:

  /devel/openwrt/staging_dir/host/bin/patch-cmdline \
  /devel/openwrt/build_dir/target-mipsel_uClibc-0.9.33.2/linux-rb532/vmlinux-initramfs \
  'root=/dev/mtdblock1 rootfstype=yaffs2 '
  Could not open kernel imagemake[5]: *** [install] Error 255

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>

SVN-Revision: 38157

target/linux/rb532/image/Makefile

@@ -63,7 +63,7 @@ define Image/Build
 	./gen_image.sh $(BIN_DIR)/$(IMG_PREFIX)-combined-$(1).bin 4 $(BIN_DIR)/$(IMG_PREFIX)-$(1).kernel $(CONFIG_TARGET_ROOTFS_PARTSIZE) $(KDIR)/root.$(1)
 endef
 
-ifneq ($(CONFIG_TARGET_ROOTFS_INITRAMFS),y)
+ifneq ($(CONFIG_TARGET_ROOTFS_INITRAMFS),)
   define Image/Prepare
 	$(STAGING_DIR_HOST)/bin/patch-cmdline $(KDIR)/vmlinux-initramfs '$(strip $(call Image/cmdline/yaffs2)) '
 	cat $(KDIR)/vmlinux-initramfs | $(STAGING_DIR_HOST)/bin/lzma e -si -so -eos -lc1 -lp2 -pb2 > $(KDIR)/vmlinux-initramfs.lzma