crda: needs threads

Because libnl needs threads, fixes:
http://autobuild.buildroot.net/results/8e32f222ddeba262ee2471d22e1c6a8afbf241c2/

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
diff --git a/package/crda/Config.in b/package/crda/Config.in
index 66baf14..539a5c7 100644
--- a/package/crda/Config.in
+++ b/package/crda/Config.in
@@ -1,5 +1,6 @@
 config BR2_PACKAGE_CRDA
 	bool "crda"
+	depends on BR2_TOOLCHAIN_HAS_THREADS # libnl
 	select BR2_PACKAGE_LIBGCRYPT
 	select BR2_PACKAGE_LIBNL
 	# regdb is a runtime dependency
@@ -13,3 +14,6 @@
 	  may operate within for a given location.
 
 	  http://linuxwireless.org/en/developers/Regulatory/CRDA
+
+comment "crda requires a toolchain with thread support"
+	depends on !BR2_TOOLCHAIN_HAS_THREADS