selftests: vm: add the "settings" file with timeout variable

The default "timeout" for one kselftest is 45 seconds, while some cases in
run_vmtests.sh require more time.  This will cause testing timeout like:

  not ok 4 selftests: vm: run_vmtests.sh # TIMEOUT 45 seconds

Therefore, add the "settings" file with timeout variable so users can set
the "timeout" value.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Patrick Wang <[email protected]>
Cc: Shuah Khan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: Patrick Wang

tools/testing/selftests/vm/settings

@@ -0,0 +1 @@
+timeout=45