Entry: Add GetEntry method

Add a GetEntry method to return the file descriptor of the Entry
log file. Even though there's a File Path property that has the
path to the Entry file, the caller may not have privileges to
access the file. This new method would allow  bmcweb to be able
to offload the Entry log file.

The Entry log file is a binary blob file and is to be opened in
read-only mode.

Change-Id: I7774f047f94d6ceaf018711660d136529be44b7f
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
diff --git a/xyz/openbmc_project/Logging/Entry.interface.yaml b/xyz/openbmc_project/Logging/Entry.interface.yaml
index 0f1953e..2f3540e 100755
--- a/xyz/openbmc_project/Logging/Entry.interface.yaml
+++ b/xyz/openbmc_project/Logging/Entry.interface.yaml
@@ -72,3 +72,13 @@
           description: >
               Information useful to developers for debugging the application.
 
+methods:
+  - name: GetEntry
+    description: >
+      Returns the file descriptor to the raw Entry file, which is a binary blob.
+      The mode of the file descriptor is to be reaad-only.
+    returns:
+      - name: fd
+        type: unixfd
+        description: >
+          The file descriptor to the Entry file.