Checkpatch: Use a Stable Version of Dependency

There is a known issue in the latest version of checkpatch dependency.
This issue would cause failure in checkpatch job.
A stable version of dependency would be used
until the issue is fixed in dependency repo.

This patch would be reverted when the issue in dependency repo is fixed.

Change-Id: I453090f628c14a15cb3aa003be3dd86664e69a09
Signed-off-by: Xinyu Zhang <xinyu.zhang@arm.com>
diff --git a/run-checkpatch.sh b/run-checkpatch.sh
index 3191194..2661332 100755
--- a/run-checkpatch.sh
+++ b/run-checkpatch.sh
@@ -104,7 +104,7 @@
 		REDIRECT=" >/dev/null"
 	fi
 
-	curl "https://raw.githubusercontent.com/torvalds/linux/master/scripts/$1" --output "$1.new" &>/dev/null
+	curl "https://raw.githubusercontent.com/torvalds/linux/v5.9/scripts/$1" --output "$1.new" &>/dev/null
 
 	if [ $? != 0 ]; then
 		app_err "curl reported error while downloading $1"