iproute2: needs mmu

Fixes
http://autobuild.buildroot.net/results/08beca1cae9dc55b2f770a01ad95bcbe56594300/

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

package/iproute2/Config.in

@@ -1,5 +1,6 @@
 config BR2_PACKAGE_IPROUTE2
 	bool "iproute2"
+	depends on BR2_USE_MMU # fork()
 	help
 	  Kernel routing and traffic control utilities.  Provides things
 	  like ip and tc.

package/openswan/Config.in

@@ -1,5 +1,6 @@
 config BR2_PACKAGE_OPENSWAN
 	bool "openswan"
+	depends on BR2_USE_MMU # iproute2
 	select BR2_PACKAGE_GMP
 	select BR2_PACKAGE_IPROUTE2
 	help