configs: galileo: correct genimage dependencies

The genimage configuration creates a vfat filesystem, so ensure we have
dosfstools / mtools built for the host.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

configs/galileo_defconfig

@@ -20,5 +20,6 @@ BR2_TARGET_ROOTFS_EXT2=y
 BR2_TARGET_ROOTFS_EXT2_4=y
 BR2_TARGET_GRUB2=y
 BR2_TARGET_GRUB2_I386_EFI=y
+BR2_PACKAGE_HOST_DOSFSTOOLS=y
 BR2_PACKAGE_HOST_GENIMAGE=y
 BR2_PACKAGE_HOST_MTOOLS=y