toolchain: do not require full path

If the toolchain can be found via $PATH, then requiring the full path to
it is unnecessary.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

package/Makefile.in

@@ -116,7 +116,11 @@ TARGET_CROSS=$(STAGING_DIR)/usr/bin/$(REAL_GNU_TARGET_NAME)-
 else ifeq ($(BR2_TOOLCHAIN_EXTERNAL),y)
 TOOLCHAIN_EXTERNAL_PREFIX:=$(call qstrip,$(BR2_TOOLCHAIN_EXTERNAL_PREFIX))
 TOOLCHAIN_EXTERNAL_PATH:=$(call qstrip,$(BR2_TOOLCHAIN_EXTERNAL_PATH))
+ifneq ($(TOOLCHAIN_EXTERNAL_PATH),)
 TARGET_CROSS=$(TOOLCHAIN_EXTERNAL_PATH)/bin/$(TOOLCHAIN_EXTERNAL_PREFIX)-
+else
+TARGET_CROSS=$(TOOLCHAIN_EXTERNAL_PREFIX)-
+endif
 else ifeq ($(BR2_TOOLCHAIN_CTNG),y)
 TARGET_CROSS=$(TOOLCHAIN_DIR)/bin/$(REAL_GNU_TARGET_NAME)-
 endif