rabbitmq-c: needs a toolchain with thread support

Fixes:
http://autobuild.buildroot.net/results/312/312f0e59e3f83868e86725ee552b320d0e739f9f/

[Peter: add autobuilder reference]
Signed-off-by: Joris Lijssens <joris.lijssens@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/rabbitmq-c/Config.in

@@ -1,7 +1,11 @@
 config BR2_PACKAGE_RABBITMQ_C
 	bool "rabbitmq-c"
+	depends on BR2_TOOLCHAIN_HAS_THREADS
 	help
 	  This is a C-language AMQP client library for use with v2.0+
 	  of the RabbitMQ broker.
 
 	  https://github.com/alanxz/rabbitmq-c
+
+comment "rabbitmq-c needs a toolchain w/ threads"
+	depends on !BR2_TOOLCHAIN_HAS_THREADS