libbpf: Update to v1.4.0

Update to the latest upstream release to include recent improvements and
bugfixes, and update copyright. Remove MAKE_VARS usage in Makefile and drop
001-cflags.patch which are no longer needed. Also add flags to disable LTO,
mistakenly dropped earlier.

Link: https://github.com/libbpf/libbpf/releases/tag/v1.4.0
Signed-off-by: Tony Ambardar <itugrok@yahoo.com>

package/libs/libbpf/Makefile

@@ -1,5 +1,5 @@
 #
-# Copyright (C) 2020-2023 Tony Ambardar <itugrok@yahoo.com>
+# Copyright (C) 2020-2024 Tony Ambardar <itugrok@yahoo.com>
 #
 # This is free software, licensed under the GNU General Public License v2.
 # See /LICENSE for more information.
@@ -8,19 +8,19 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=libbpf
-PKG_VERSION:=1.3.0
+PKG_VERSION:=1.4.0
 PKG_RELEASE:=1
 
 PKG_SOURCE_URL:=https://github.com/libbpf/libbpf
-PKG_MIRROR_HASH:=669d8db696f86f640f86edc358bffa2af8dda656b8e787b095de3578bd8d94ff
+PKG_MIRROR_HASH:=4c37636699c604de345937bdbdf8f2e6ce69cbf768a4aa669c32b542e5302de6
 PKG_SOURCE_PROTO:=git
-PKG_SOURCE_VERSION:=v1.3.0
+PKG_SOURCE_VERSION:=v1.4.0
 PKG_ABI_VERSION:=$(firstword $(subst .,$(space),$(PKG_VERSION)))
 
 PKG_MAINTAINER:=Tony Ambardar <itugrok@yahoo.com>
 PKG_CPE_ID:=cpe:/a:libbpf_project:libbpf
 
-PKG_BUILD_FLAGS:=no-mips16
+PKG_BUILD_FLAGS:=no-mips16 no-gc-sections no-lto
 PKG_BUILD_PARALLEL:=1
 PKG_INSTALL:=1
 
@@ -41,10 +41,6 @@ define Package/libbpf/description
   libbpf is a library for loading eBPF programs and reading and manipulating eBPF objects from user-space.
 endef
 
-MAKE_VARS = \
-	EXTRA_CFLAGS="$(TARGET_CFLAGS) $(TARGET_CPPFLAGS)" \
-	LDFLAGS="$(TARGET_LDFLAGS)"
-
 MAKE_FLAGS += \
 	$(if $(findstring c,$(OPENWRT_VERBOSE)),V=1,V='') \
 	LIBSUBDIR=lib

package/libs/libbpf/patches/001-cflags.patch

@@ -1,10 +0,0 @@
---- a/src/Makefile
-+++ b/src/Makefile
-@@ -34,6 +34,7 @@ ALL_CFLAGS := $(INCLUDES)
- 
- SHARED_CFLAGS += -fPIC -fvisibility=hidden -DSHARED
- 
-+CFLAGS = $(EXTRA_CFLAGS)
- CFLAGS ?= -g -O2 -Werror -Wall -std=gnu89
- ALL_CFLAGS += $(CFLAGS) 						\
- 	      -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64		\