mips: delete duplicated BUILTIN_DTB and LIBFDT configs

CONFIG_BUILTIN_DTB and CONFIG_LIBFDT selection is duplicated
in menu "Machine selection" under MIPS_MALTA.
Signed-off-by: Maksym Kokhan <maksym.kokhan@globallogic.com>
Signed-off-by: Andrii Bordunov <andrew.bordunov@gmail.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21100/
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org

arch/mips/Kconfig

@@ -540,8 +540,6 @@ config MIPS_MALTA
 	select USE_OF
 	select LIBFDT
 	select ZONE_DMA32 if 64BIT
-	select BUILTIN_DTB
-	select LIBFDT
 	help
 	  This enables support for the MIPS Technologies Malta evaluation
 	  board.