test: Fix typos in comments

Fix some typos in various files introduced with the vboot test conversion.

Reported-by: Teddy Reed <teddy.reed@gmail.com>

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/test/py/u_boot_utils.py b/test/py/u_boot_utils.py
index d71348f..e74e342 100644
--- a/test/py/u_boot_utils.py
+++ b/test/py/u_boot_utils.py
@@ -186,7 +186,7 @@
     return run_and_log(u_boot_console, cmd_str.split())
 
 def run_and_log_expect_exception(u_boot_console, cmd, retcode, msg):
-    """Run a command which is expected to fail.
+    """Run a command that is expected to fail.
 
     This runs a command and checks that it fails with the expected return code
     and exception method. If not, an exception is raised.
@@ -195,7 +195,7 @@
         u_boot_console: A console connection to U-Boot.
         cmd: The command to run, as an array of argv[].
         retcode: Expected non-zero return code from the command.
-        msg: String which should be contained within the command's output.
+        msg: String that should be contained within the command's output.
     """
     try:
         runner = u_boot_console.log.get_runner(cmd[0], sys.stdout)