fix an arch/alpha/Kconfig typo

	bool "Discontiguous Memory Support (EXPERIMENTAL)"

	depends on EXPERIMENTAL

	help

	  Say Y to upport efficient handling of discontiguous physical memory,

	  Say Y to support efficient handling of discontiguous physical memory,

	  for architectures which are either NUMA (Non-Uniform Memory Access)

	  or have huge holes in the physical address space for other reasons.

	  See <file:Documentation/vm/numa> for more.