sh: Support variable page sizes on nommu.

PAGE_SIZE doesn't need to be fixed at 4096 on nommu, so stub in a !MMU
case for the various PAGE_SIZE Kconfig options.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/mm/Kconfig

@@ -145,19 +145,19 @@ choice
 
 config PAGE_SIZE_4KB
 	bool "4kB"
-	depends on !X2TLB
+	depends on !MMU || !X2TLB
 	help
 	  This is the default page size used by all SuperH CPUs.
 
 config PAGE_SIZE_8KB
 	bool "8kB"
-	depends on X2TLB
+	depends on !MMU || X2TLB
 	help
 	  This enables 8kB pages as supported by SH-X2 and later MMUs.
 
 config PAGE_SIZE_64KB
 	bool "64kB"
-	depends on CPU_SH4 || CPU_SH5
+	depends on !MMU || CPU_SH4 || CPU_SH5
 	help
 	  This enables support for 64kB pages, possible on all SH-4
 	  CPUs and later.