iproute2: add libcap support, enabled in ip-full

Preserve optionality of libcap by having configuration script follow the
HAVE_CAP environment variable, used similarly to the HAVE_ELF variable.

Signed-off-by: Alin Nastac <alin.nastac@gmail.com>
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com> [PKG_RELEASE increase/refresh patches]
(backported from commit a6da3f9ef7)
Signed-off-by: Jo-Philipp Wich <jo@mein.io>

package/network/utils/iproute2/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=iproute2
 PKG_VERSION:=5.0.0
-PKG_RELEASE:=2
+PKG_RELEASE:=2.1
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.xz
 PKG_SOURCE_URL:=@KERNEL/linux/utils/net/iproute2
@@ -49,7 +49,7 @@ $(call Package/iproute2/Default)
  VARIANT:=full
  PROVIDES:=ip
  ALTERNATIVES:=300:/sbin/ip:/usr/libexec/ip-full
- DEPENDS:=+libnl-tiny +libelf +(PACKAGE_devlink||PACKAGE_rdma):libmnl
+ DEPENDS:=+libnl-tiny +libelf +(PACKAGE_devlink||PACKAGE_rdma):libmnl +libcap
 endef
 
 define Package/tc
@@ -57,43 +57,43 @@ $(call Package/iproute2/Default)
   TITLE:=Traffic control utility
   VARIANT:=tc
   PROVIDES:=tc
-  DEPENDS:=+kmod-sched-core +libxtables +libelf +(PACKAGE_devlink||PACKAGE_rdma):libmnl
+  DEPENDS:=+kmod-sched-core +libxtables +libelf +(PACKAGE_devlink||PACKAGE_rdma):libmnl +PACKAGE_ip-full:libcap
 endef
 
 define Package/genl
 $(call Package/iproute2/Default)
   TITLE:=General netlink utility frontend
-  DEPENDS:=+libnl-tiny +(PACKAGE_devlink||PACKAGE_rdma):libmnl +(PACKAGE_tc||PACKAGE_ip-full):libelf
+  DEPENDS:=+libnl-tiny +(PACKAGE_devlink||PACKAGE_rdma):libmnl +(PACKAGE_tc||PACKAGE_ip-full):libelf +PACKAGE_ip-full:libcap
 endef
 
 define Package/ip-bridge
 $(call Package/iproute2/Default)
   TITLE:=Bridge configuration utility from iproute2
-  DEPENDS:=+libnl-tiny +(PACKAGE_devlink||PACKAGE_rdma):libmnl +(PACKAGE_tc||PACKAGE_ip-full):libelf
+  DEPENDS:=+libnl-tiny +(PACKAGE_devlink||PACKAGE_rdma):libmnl +(PACKAGE_tc||PACKAGE_ip-full):libelf +PACKAGE_ip-full:libcap
 endef
 
 define Package/ss
 $(call Package/iproute2/Default)
   TITLE:=Socket statistics utility
-  DEPENDS:=+libnl-tiny +(PACKAGE_devlink||PACKAGE_rdma):libmnl +(PACKAGE_tc||PACKAGE_ip-full):libelf
+  DEPENDS:=+libnl-tiny +(PACKAGE_devlink||PACKAGE_rdma):libmnl +(PACKAGE_tc||PACKAGE_ip-full):libelf +PACKAGE_ip-full:libcap
 endef
 
 define Package/nstat
 $(call Package/iproute2/Default)
   TITLE:=Network statistics utility
-  DEPENDS:=+libnl-tiny +(PACKAGE_devlink||PACKAGE_rdma):libmnl +(PACKAGE_tc||PACKAGE_ip-full):libelf
+  DEPENDS:=+libnl-tiny +(PACKAGE_devlink||PACKAGE_rdma):libmnl +(PACKAGE_tc||PACKAGE_ip-full):libelf +PACKAGE_ip-full:libcap
 endef
 
 define Package/devlink
 $(call Package/iproute2/Default)
   TITLE:=Network devlink utility
-  DEPENDS:=+libmnl +(PACKAGE_tc||PACKAGE_ip-full):libelf
+  DEPENDS:=+libmnl +(PACKAGE_tc||PACKAGE_ip-full):libelf +PACKAGE_ip-full:libcap
 endef
 
 define Package/rdma
 $(call Package/iproute2/Default)
   TITLE:=Network rdma utility
-  DEPENDS:=+libmnl +(PACKAGE_tc||PACKAGE_ip-full):libelf
+  DEPENDS:=+libmnl +(PACKAGE_tc||PACKAGE_ip-full):libelf +PACKAGE_ip-full:libcap
 endef
 
 ifeq ($(BUILD_VARIANT),tiny)
@@ -102,6 +102,7 @@ endif
 
 ifeq ($(BUILD_VARIANT),full)
   HAVE_ELF:=y
+  HAVE_CAP:=y
 endif
 
 ifeq ($(BUILD_VARIANT),tc)
@@ -132,6 +133,7 @@ MAKE_FLAGS += \
 	IP_CONFIG_TINY=$(IP_CONFIG_TINY) \
 	HAVE_ELF=$(HAVE_ELF) \
 	HAVE_MNL=$(HAVE_MNL) \
+	HAVE_CAP=$(HAVE_CAP) \
 	IPT_LIB_DIR=/usr/lib/iptables \
 	XT_LIB_DIR=/usr/lib/iptables \
 	FPIC="$(FPIC)"

package/network/utils/iproute2/patches/150-keep_libcap_optional.patch

@@ -0,0 +1,11 @@
+--- a/configure
++++ b/configure
+@@ -313,7 +313,7 @@ EOF
+ 
+ check_cap()
+ {
+-	if ${PKG_CONFIG} libcap --exists; then
++	if [ "${HAVE_CAP}" = "y" ] && ${PKG_CONFIG} libcap --exists; then
+ 		echo "HAVE_CAP:=y" >>$CONFIG
+ 		echo "yes"
+