package/libyang: needs __sync_*_4 intrinsics

libyang needs __sync_*_4 intrinsics since bump to version 2.0.112 in
commit 2a3edc5e00b38f4f927894d0911990c9060e4415 and
https://github.com/CESNET/libyang/commit/080064b7906aecd7454e58e1c34c1c2198809e4e:

/home/buildroot/autobuild/instance-3/output-1/host/opt/ext-toolchain/bin/../lib/gcc/sparc-buildroot-linux-uclibc/9.3.0/../../../../sparc-buildroot-linux-uclibc/bin/ld: ../../libyang.so.2.13.7: undefined reference to `__sync_fetch_and_sub_4'

Fixes:
 - http://autobuild.buildroot.org/results/c1f090bde4891ac1cc84e59c51ff9561869d42b9

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

package/frr/Config.in

@@ -3,7 +3,7 @@ config BR2_PACKAGE_FRR
 	depends on BR2_TOOLCHAIN_HAS_THREADS
 	depends on !BR2_STATIC_LIBS # libyang
 	depends on BR2_USE_MMU # fork()
-	depends on BR2_TOOLCHAIN_HAS_SYNC_4 # json-c
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4 # json-c, libyang
 	select BR2_PACKAGE_BASH
 	select BR2_PACKAGE_BUSYBOX_SHOW_OTHERS # bash
 	select BR2_PACKAGE_C_ARES

package/libnetconf2/Config.in

@@ -1,5 +1,6 @@
 config BR2_PACKAGE_LIBNETCONF2
 	bool "libnetconf2"
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4 # libyang
 	depends on BR2_TOOLCHAIN_HAS_THREADS
 	depends on !BR2_STATIC_LIBS
 	depends on BR2_USE_MMU
@@ -12,4 +13,5 @@ config BR2_PACKAGE_LIBNETCONF2
 
 comment "libnetconf2 needs a toolchain w/ threads, dynamic libraray"
 	depends on BR2_USE_MMU
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4
 	depends on BR2_STATIC_LIBS || !BR2_TOOLCHAIN_HAS_THREADS

package/libyang/Config.in

@@ -1,5 +1,6 @@
 config BR2_PACKAGE_LIBYANG
 	bool "libyang"
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4 # __sync_*_4 intrinsics
 	depends on BR2_TOOLCHAIN_HAS_THREADS
 	depends on !BR2_STATIC_LIBS
 	select BR2_PACKAGE_PCRE2
@@ -10,4 +11,5 @@ config BR2_PACKAGE_LIBYANG
 	  https://github.com/CESNET/libyang
 
 comment "libyang needs a toolchain w/ threads, dynamic library"
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4
 	depends on !BR2_TOOLCHAIN_HAS_THREADS || BR2_STATIC_LIBS

package/netopeer2/Config.in

@@ -1,11 +1,13 @@
 comment "netopeer2 needs a toolchain w/ gcc >= 4.8, C++, threads, dynamic library"
 	depends on BR2_USE_MMU
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4
 	depends on BR2_STATIC_LIBS || !BR2_INSTALL_LIBSTDCPP \
 		|| !BR2_TOOLCHAIN_HAS_THREADS_NPTL || !BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
 
 config BR2_PACKAGE_NETOPEER2
 	bool "netopeer2"
 	depends on BR2_USE_MMU # libnetconf2, libssh, sysrepo
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4 # libyang
 	depends on !BR2_STATIC_LIBS # libnetconf2, libssh, libyang, sysrepo
 	depends on BR2_INSTALL_LIBSTDCPP # sysrepo
 	depends on BR2_TOOLCHAIN_HAS_THREADS_NPTL

package/sysrepo/Config.in

@@ -1,6 +1,7 @@
 config BR2_PACKAGE_SYSREPO
 	bool "sysrepo"
 	depends on BR2_USE_MMU
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4 # libyang
 	depends on !BR2_STATIC_LIBS
 	depends on BR2_INSTALL_LIBSTDCPP
 	depends on BR2_TOOLCHAIN_HAS_THREADS_NPTL
@@ -24,5 +25,6 @@ endif
 
 comment "sysrepo needs a toolchain w/ C++, NPTL, dynamic library, gcc >= 4.8"
 	depends on BR2_USE_MMU
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4
 	depends on BR2_STATIC_LIBS || !BR2_INSTALL_LIBSTDCPP \
 		|| !BR2_TOOLCHAIN_HAS_THREADS_NPTL