[openwrt/openwrt] bpftools: fix libbpf pkgconfig file

[LEDE Commits]

hauke pushed a commit to openwrt/openwrt.git, branch openwrt-21.02:
https://git.openwrt.org/6b2bcd2597688484007349243ac4cd835b2a5cd2

commit 6b2bcd2597688484007349243ac4cd835b2a5cd2
Author: Tony Ambardar <itugrok at yahoo.com>
AuthorDate: Mon Mar 1 01:07:45 2021 -0800

    bpftools: fix libbpf pkgconfig file
    
    The pkgconfig file hardcodes a host library directory which cannot be
    overridden by OpenWrt during builds. Use SED to fix this and potential
    include directory problems, as is done with several other packages.
    
    This fixes a strange issue intermittently seen building iproute2 on the
    oxnas target:
    
    iptables modules directory: /usr/lib/iptables
    libc has setns: yes
    SELinux support: no
    libbpf support: no
            libbpf version 0.3.0 is too low, please update it to at least 0.1.0
            LIBBPF_FORCE=on set, but couldn't find a usable libbpf
    
    Fixes: 2f0d672088c3 ("bpftools: add utility and library packages
    supporting eBPF usage")
    Reported-by: Russell Senior <russell at personaltelco.net>
    Signed-off-by: Tony Ambardar <itugrok at yahoo.com>
    (cherry picked from commit 9e64e4ce26719ea81637b0e3d9754bd5190f0c21)
---
 package/network/utils/bpftools/Makefile | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/package/network/utils/bpftools/Makefile b/package/network/utils/bpftools/Makefile
index 7a25b35755..ab1e4aa0c4 100644
--- a/package/network/utils/bpftools/Makefile
+++ b/package/network/utils/bpftools/Makefile
@@ -145,6 +145,10 @@ define Build/InstallDev/libbpf
 	$(INSTALL_DIR) $(1)/usr/lib/pkgconfig
 	$(CP) $(PKG_INSTALL_DIR)/usr/lib$(LIB_SUFFIX)/pkgconfig/libbpf.pc \
 		$(1)/usr/lib/pkgconfig/
+	$(SED) 's,/usr/include,$$$${prefix}/include,g' \
+		$(1)/usr/lib/pkgconfig/libbpf.pc
+	$(SED) 's,/usr/lib,$$$${exec_prefix}/lib,g' \
+		$(1)/usr/lib/pkgconfig/libbpf.pc
 endef
 
 ifeq ($(BUILD_VARIANT),lib)