perf: add dependency on !LINUX_3_18 to fix builds

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

SVN-Revision: 48720

package/devel/perf/Makefile

@@ -25,7 +25,7 @@ include $(INCLUDE_DIR)/package.mk
 define Package/perf
   SECTION:=devel
   CATEGORY:=Development
-  DEPENDS:= +libelf1 +libdw +libpthread +librt +objdump
+  DEPENDS:= +libelf1 +libdw +libpthread +librt +objdump @!LINUX_3_18
   TITLE:=Linux performance monitoring tool
   VERSION:=$(LINUX_VERSION)-$(PKG_RELEASE)
   URL:=http://www.kernel.org