um: drop unused Kconfig symbol

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Michal Marek <mmarek@suse.cz>

arch/um/Kconfig.x86

@@ -53,9 +53,6 @@ config ARCH_HAS_SC_SIGNALS
 config ARCH_REUSE_HOST_VSYSCALL_AREA
 	def_bool !64BIT
 
-config SMP_BROKEN
-	def_bool 64BIT
-
 config GENERIC_HWEIGHT
 	def_bool y