kconfig: include kernel/Kconfig.preempt from init/Kconfig

Almost all architectures include it.  Add a ARCH_NO_PREEMPT symbol to
disable preempt support for alpha, hexagon, non-coldfire m68k and
user mode Linux.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/arch/Kconfig b/arch/Kconfig
index 09a561a..cddd0fa 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -881,6 +881,9 @@
 config ARCH_NO_COHERENT_DMA_MMAP
 	bool
 
+config ARCH_NO_PREEMPT
+	bool
+
 config CPU_NO_EFFICIENT_FFS
 	def_bool n