cannelloni: needs gcc >= 4.8

Uses C++11, fixes:
http://autobuild.buildroot.net/results/4a9/4a9999555c20e495d4981deafc2960940e67febe/

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/cannelloni/Config.in

@@ -1,5 +1,6 @@
 config BR2_PACKAGE_CANNELLONI
 	bool "cannelloni"
+	depends on BR2_TOOLCHAIN_GCC_AT_LEAST_4_8 # C++11
 	depends on BR2_INSTALL_LIBSTDCPP
 	depends on BR2_USE_MMU # lksctp-tools
 	depends on BR2_TOOLCHAIN_HAS_THREADS # lksctp-tools
@@ -10,6 +11,7 @@ config BR2_PACKAGE_CANNELLONI
 
 	  https://github.com/mguentner/cannelloni
 
-comment "cannelloni needs a toolchain w/ C++, threads"
-	depends on !BR2_INSTALL_LIBSTDCPP || !BR2_TOOLCHAIN_HAS_THREADS
+comment "cannelloni needs a toolchain w/ C++, threads, gcc >= 4.8"
+	depends on !BR2_INSTALL_LIBSTDCPP || \
+	!BR2_TOOLCHAIN_GCC_AT_LEAST_4_8 || !BR2_TOOLCHAIN_HAS_THREADS
 	depends on BR2_USE_MMU