sofia-sip: needs threads

Fixes:
http://autobuild.buildroot.net/results/1e8/1e8c466b7a65b8e70f3318ab1a5bad79468f5efd

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/sofia-sip/Config.in

@@ -1,5 +1,6 @@
 config BR2_PACKAGE_SOFIA_SIP
 	bool "sofia-sip"
+	depends on BR2_TOOLCHAIN_HAS_THREADS
 	help
 	  Sofia-SIP is an open-source SIP User-Agent library,
 	  compliant with the IETF RFC3261 specification (see the
@@ -8,3 +9,6 @@ config BR2_PACKAGE_SOFIA_SIP
 	  real-time and person-to-person communication services.
 
 	  http://sofia-sip.sourceforge.net/
+
+comment "sofia-sip needs a toolchain w/ threads"
+	depends on !BR2_TOOLCHAIN_HAS_THREADS