luafilesystem: tweak Config.in

Print a comment if largefile isn't available, and use select rather than
depends for the lua shared library option.

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

package/luafilesystem/Config.in

@@ -1,9 +1,12 @@
 config BR2_PACKAGE_LUAFILESYSTEM
 	bool "luafilesystem"
 	depends on BR2_LARGEFILE
-	depends on BR2_PACKAGE_LUA_SHARED_LIBRARY
+	select BR2_PACKAGE_LUA_SHARED_LIBRARY
 	help
 	  LuaFileSystem offers a portable way to access
 	  the underlying directory structure and file attributes.
 
 	  http://luaforge.net/projects/luafilesystem/
+
+comment "luafilesystem requires a toolchain with LARGEFILE support"
+	depends on !BR2_LARGEFILE