[XS] Change in coreboot[master]: docs/flashmap: Document available flashmap flags

[Hung-Te Lin (Code Review)]

Hung-Te Lin has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/75850?usp=email )

Change subject: docs/flashmap: Document available flashmap flags
......................................................................

docs/flashmap: Document available flashmap flags

Add the missing flag 'PRESERVE' that was introduced from
https://review.coreboot.org/c/coreboot/+/31766.

Change-Id: Iada0fcb0ada1573acfbb51b5f6bf723fb8b68ba8
Signed-off-by: Hung-Te Lin 
---
M Documentation/lib/flashmap.md
1 file changed, 4 insertions(+), 3 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/50/75850/1

diff --git a/Documentation/lib/flashmap.md b/Documentation/lib/flashmap.md
index f0816cf..8b8acc8 100644
--- a/Documentation/lib/flashmap.md
+++ b/Documentation/lib/flashmap.md
@@ -111,9 +111,10 @@
 * Just because something is noted as optional doesn't mean it is in every case:
   the answer might actually depend on which other information is---or
   isn't---provided.
-* The "flag" specifies the attribute or type for given section. The most
-  important supported flag is "CBFS", which indicates the section will contain
-  a CBFS structure.
+* The "flag" specifies the attribute or type for given section. That includes:
+  * `CBFS`: indicates the section will contain a CBFS structure.
+  * `PRESERVE`: the contents must be preserved during firmware update or
+    recovery.
 * In particular, it is only legal to place a (CBFS) flag on a leaf section; that
   is, choosing to add child sections excludes the possibility of putting a CBFS
   in their parent. Such flags are only used to decide where CBFS empty file