arch: Add generic Kconfig option indicating page size smaller than 64k

NTFS_RW and VMXNET3 require a page size smaller than 64kB.  Add generic
Kconfig option for use outside architecture code to avoid architecture
specific Kconfig options in that code.
Suggested-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Cc: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arch/Kconfig

@@ -991,6 +991,16 @@ config HAVE_ARCH_COMPAT_MMAP_BASES
 	  and vice-versa 32-bit applications to call 64-bit mmap().
 	  Required for applications doing different bitness syscalls.
 
+config PAGE_SIZE_LESS_THAN_64KB
+	def_bool y
+	depends on !ARM64_64K_PAGES
+	depends on !IA64_PAGE_SIZE_64KB
+	depends on !PAGE_SIZE_64KB
+	depends on !PARISC_PAGE_SIZE_64KB
+	depends on !PPC_64K_PAGES
+	depends on !PPC_256K_PAGES
+	depends on !PAGE_SIZE_256KB
+
 # This allows to use a set of generic functions to determine mmap base
 # address by giving priority to top-down scheme only if the process
 # is not in legacy mode (compat task, unlimited stack size or