ARM: LPC32xx: defconfig update: Remove the museum NAND option

The MTD_NAND_MUSEUM_IDS configuration options was removed - update the
lpc32xx_defconfig file.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: Roland Stigge <stigge@antcom.de>