hiawatha: needs threads

Fixes
http://autobuild.buildroot.net/results/9bb3bdb9de43fc6bab119674885df2a28e5559ee/

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/hiawatha/Config.in

@@ -1,7 +1,11 @@
+comment "hiawatha requires a toolchain with thread support"
+	depends on !BR2_TOOLCHAIN_HAS_THREADS
+
 config BR2_PACKAGE_HIAWATHA
 	bool "hiawatha"
 	# needs fork()
 	depends on BR2_USE_MMU
+	depends on BR2_TOOLCHAIN_HAS_THREADS
 	help
 	  Hiawatha is a webserver for Unix and has been built with
 	  security in mind. This resulted in a highly secure