package/kvazaar: needs BR2_TOOLCHAIN_HAS_SYNC_4

./.libs/libkvazaar.so: undefined reference to `__sync_add_and_fetch_4'

Fixes:
http://autobuild.buildroot.net/results/b39/b39a82a2e4106c5ec55c288415e73043a872a0b1

Signed-off-by: Romain Naour <romain.naour@smile.fr>
Reviewed-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/kvazaar/Config.in

@@ -2,10 +2,12 @@ config BR2_PACKAGE_KVAZAAR
 	bool "kvazaar"
 	depends on BR2_INSTALL_LIBSTDCPP
 	depends on BR2_TOOLCHAIN_HAS_THREADS
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4
 	help
 	  An open-source HEVC encoder licensed under LGPLv2.1
 
 	  https://github.com/ultravideo/kvazaar
 
 comment "kvazaar needs a toolchain w/ C++, threads"
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4
 	depends on !BR2_INSTALL_LIBSTDCPP || !BR2_TOOLCHAIN_HAS_THREADS