infra/common: document the use of --depth parameter for repo init

There have been reports of sync failure specifically for linux kernel.
In order to workaround such a failure if it occurs, the use of --depth
parameter for the repo init command has been documented. With depth set
to 1 (--depth=1), the commit history that is download is reduced to just
one commit and this reduces the overall sync time and reduces failure to
sync the linux kernel source.
Signed-off-by: Thomas Abraham <thomas.abraham@arm.com>
Change-Id: I726e20124804b02514172cdee27a132c3acb22dd

docs/infra/common/download-sources.rst

@@ -115,6 +115,10 @@ This section explains the procedure to sync the software stack.
   repo init command will fail to complete. Refer the `troubleshooting guide`_
   on resolving this issue.
 
+  Note: In order to reduce the size of the commit history that is downloaded
+  (and reduce the time taken to download the platform software stack), append
+  "--depth=1" to the repo init command (without the quotes).
+
 
 Installing prerequisites
 ------------------------

docs/infra/common/troubleshooting-guide.rst

@@ -80,6 +80,16 @@ rechecked. This issue is typically seen if the host machine has a
 configuration below that of on the one listed at `recommended configuration`_.
 
 
+Repo sync fails when downloading linux repo
+-------------------------------------------
+
+If the download of the linux repo fails during the execution of the 'repo sync'
+command, rerun the repo init command with the "--depth=1" (without the quotes)
+parameter appended to the repo init command. The parameter "--depth=1" reduces
+the commit history that is downloaded and can reduce the failures in
+downloading linux repo.
+
+
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