toolchain/gcc: fix target-gcc selects

We need to select BR2_PACKAGE_BINUTILS as well, now
BINUTILS_TARGET depends on it.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

toolchain/gcc/Config.in.2

@@ -1,6 +1,7 @@
 config BR2_PACKAGE_GCC_TARGET
 	bool "native toolchain in the target filesystem"
 	depends on BR2_HAVE_DEVFILES
+	select BR2_PACKAGE_BINUTILS
 	select BR2_PACKAGE_BINUTILS_TARGET
 	select BR2_PACKAGE_MPC if BR2_GCC_VERSION_4_5_X
 	select BR2_PACKAGE_MPFR