linux: qstrip the custom DTS path

This fixes a problem reported by wacha@mit.bme.hu, see
http://lists.busybox.net/pipermail/buildroot/2013-June/073312.html.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

linux/linux.mk

@@ -55,7 +55,7 @@ LINUX_VERSION_PROBED = $(shell $(MAKE) $(LINUX_MAKE_FLAGS) -C $(LINUX_DIR) --no-
 ifeq ($(BR2_LINUX_KERNEL_USE_INTREE_DTS),y)
 KERNEL_DTS_NAME = $(call qstrip,$(BR2_LINUX_KERNEL_INTREE_DTS_NAME))
 else ifeq ($(BR2_LINUX_KERNEL_USE_CUSTOM_DTS),y)
-KERNEL_DTS_NAME = $(basename $(notdir $(BR2_LINUX_KERNEL_CUSTOM_DTS_PATH)))
+KERNEL_DTS_NAME = $(basename $(notdir $(call qstrip,$(BR2_LINUX_KERNEL_CUSTOM_DTS_PATH))))
 endif
 
 ifeq ($(BR2_LINUX_KERNEL_DTS_SUPPORT)$(KERNEL_DTS_NAME),y)