Doc: Update Redfish.md with storage/drive info

The API for "/redfish/v1/Systems/system/Storage/1/Drives/<str>" was not
in the Redfish.md document. This change adds some documentation about
what is expected from this URI.

Change-Id: I4842254c3d35bf312ba71b745e8640df9866ca7a
Signed-off-by: John Edward Broadbent <jebr@google.com>
diff --git a/Redfish.md b/Redfish.md
index ab4f7db..694a587 100644
--- a/Redfish.md
+++ b/Redfish.md
@@ -690,6 +690,12 @@
 - Drives@odata.count
 - Status
 
+#### /redfish/v1/Systems/system/Storage/{StorageId}/Drive/{DriveId}/
+##### Storage
+- CapacityBytes
+- Links
+- Status
+
 #### /redfish/v1/TaskService/
 ##### TaskService
 - CompletedTaskOverWritePolicy