memblock: add NO_BOOTMEM config symbol

With the NO_BOOTMEM symbol added architectures may now use the following
syntax to tell that they do not need bootmem:

	select NO_BOOTMEM

This is much more convinient than adding a new kconfig symbol which was
otherwise required.

Adding this symbol does not conflict with the architctures that already
define their own symbol.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/Kconfig b/mm/Kconfig
index f2f1ca1..011b110 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -131,6 +131,9 @@
 config HAVE_MEMBLOCK
 	boolean
 
+config NO_BOOTMEM
+	boolean
+
 # eventually, we can have this option just 'select SPARSEMEM'
 config MEMORY_HOTPLUG
 	bool "Allow for memory hot-add"