[U-Boot] [PATCH] Makefile: fix clobber target

[Andreas Bießmann]

Remove the $(CONFIG_SPL_TARGET) from ALL-y if not set. This prevents following
warning:

---8<---
abiessmann at punisher % ./MAKEALL -a arm -s omap3
rm: cannot remove `/tmp/build_test/eco5pk/': Is a directory
make: *** [clobber] Error 1
rm: cannot remove `/tmp/build_test/omap3_overo/': Is a directory
make: *** [clobber] Error 1
--->8---

Signed-off-by: Andreas Bießmann <andreas.devel at googlemail.com>
---
 Makefile |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/Makefile b/Makefile
index d60a14b..5302c0a 100644
--- a/Makefile
+++ b/Makefile
@@ -406,7 +406,9 @@ ALL-y += $(obj)u-boot.srec $(obj)u-boot.bin $(obj)System.map
 ALL-$(CONFIG_NAND_U_BOOT) += $(obj)u-boot-nand.bin
 ALL-$(CONFIG_ONENAND_U_BOOT) += $(obj)u-boot-onenand.bin
 ALL-$(CONFIG_SPL) += $(obj)spl/u-boot-spl.bin
+ifneq ($(CONFIG_SPL_TARGET),)
 ALL-$(CONFIG_SPL) += $(obj)$(subst ",,$(CONFIG_SPL_TARGET))
+endif
 ALL-$(CONFIG_OF_SEPARATE) += $(obj)u-boot.dtb $(obj)u-boot-dtb.bin
 
 # enable combined SPL/u-boot/dtb rules for tegra
-- 
1.7.10.4