package/binutils: use the Xtensa variables

... instead of re-computing them over-and-over-again.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/binutils/binutils.mk

@@ -121,11 +121,9 @@ define BINUTILS_INSTALL_TARGET_CMDS
 endef
 endif
 
-XTENSA_CORE_NAME = $(call qstrip, $(BR2_XTENSA_CORE_NAME))
-ifneq ($(XTENSA_CORE_NAME),)
+ifneq ($(ARCH_XTENSA_CORE_NAME),)
 define BINUTILS_XTENSA_PRE_PATCH
-	tar xf $(BR2_XTENSA_OVERLAY_DIR)/xtensa_$(XTENSA_CORE_NAME).tar \
-		-C $(@D) --strip-components=1 binutils
+	tar xf $(ARCH_XTENSA_OVERLAY_TAR) -C $(@D) --strip-components=1 binutils
 endef
 BINUTILS_PRE_PATCH_HOOKS += BINUTILS_XTENSA_PRE_PATCH
 HOST_BINUTILS_PRE_PATCH_HOOKS += BINUTILS_XTENSA_PRE_PATCH