kselftest: amd-pstate: Fix spelling mistakes

Fix spelling mistakes in run.sh "drvier" => "driver" and
in gitsource.sh "senconds" => "seconds".

Signed-off-by: Sukrut Bellary <sukrut.bellary@gmail.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>