package/python-iptables: add explicit dependency on dynamic libs

The package uses ctypes.CDLL extensively which only makes sense when dynamic
libraries are available.

Signed-off-by: Frank Vanbever <frank.vanbever@essensium.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
(cherry picked from commit 21b85bc56cdcf030cced57dea0f78cdce59912b8)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/python-iptables/Config.in

@@ -1,7 +1,11 @@
 config BR2_PACKAGE_PYTHON_IPTABLES
 	bool "python-iptables"
+	depends on !BR2_STATIC_LIBS
 	select BR2_PACKAGE_IPTABLES # runtime dependency
 	help
 	  Python bindings for iptables.
 
 	  https://github.com/ldx/python-iptables
+
+comment "python-iptables needs a toolchain w/ dynamic library"
+	depends on BR2_STATIC_LIBS