lmb: add a flag to allow suppressing memory map change notification

Add a flag LMB_NONOTIFY that can be passed to the LMB API's for
reserving memory. This will then result in no notification being sent
from the LMB module for the changes to the LMB's memory map.

While here, also add a description of the memory attributes that the
flags signify.

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>

include/lmb.h

@@ -18,11 +18,14 @@
  * enum lmb_flags - definition of memory region attributes
  * @LMB_NONE: no special request
  * @LMB_NOMAP: don't add to mmu configuration
+ * @LMB_NOOVERWRITE: the memory region cannot be overwritten/re-reserved
+ * @LMB_NONOTIFY: do not notify other modules of changes to this memory region
  */
 enum lmb_flags {
 	LMB_NONE		= 0,
 	LMB_NOMAP		= BIT(1),
 	LMB_NOOVERWRITE		= BIT(2),
+	LMB_NONOTIFY		= BIT(3),
 };
 
 /**