[ALPHA] Remove SBUS & MCA from alpha Kconfig.

From Matthew Wilcox <willy@debian.org>.

arch/alpha/Kconfig

@@ -269,17 +269,6 @@ config ISA
 	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
 	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
 
-config SBUS
-	bool
-
-config MCA
-	bool
-	help
-	  MicroChannel Architecture is found in some IBM PS/2 machines and
-	  laptops.  It is a bus system similar to PCI or ISA. See
-	  <file:Documentation/mca.txt> (and especially the web page given
-	  there) before attempting to build an MCA bus kernel.
-
 config PCI
 	bool
 	depends on !ALPHA_JENSEN