test/py: use " for docstrings

Python's coding style docs indicate to use " not ' for docstrings.

test/py has other violations of the coding style docs, since the docs
specify a stranger style than I would expect, but nobody has complained
about those yet:-)

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/test/py/u_boot_spawn.py b/test/py/u_boot_spawn.py
index df4c675..d508075 100644
--- a/test/py/u_boot_spawn.py
+++ b/test/py/u_boot_spawn.py
@@ -12,23 +12,23 @@
 import time
 
 class Timeout(Exception):
-    '''An exception sub-class that indicates that a timeout occurred.'''
+    """An exception sub-class that indicates that a timeout occurred."""
     pass
 
 class Spawn(object):
-    '''Represents the stdio of a freshly created sub-process. Commands may be
+    """Represents the stdio of a freshly created sub-process. Commands may be
     sent to the process, and responses waited for.
-    '''
+    """
 
     def __init__(self, args):
-        '''Spawn (fork/exec) the sub-process.
+        """Spawn (fork/exec) the sub-process.
 
         Args:
             args: array of processs arguments. argv[0] is the command to execute.
 
         Returns:
             Nothing.
-        '''
+        """
 
         self.waited = False
         self.buf = ''
@@ -56,26 +56,26 @@
         self.poll.register(self.fd, select.POLLIN | select.POLLPRI | select.POLLERR | select.POLLHUP | select.POLLNVAL)
 
     def kill(self, sig):
-        '''Send unix signal "sig" to the child process.
+        """Send unix signal "sig" to the child process.
 
         Args:
             sig: The signal number to send.
 
         Returns:
             Nothing.
-        '''
+        """
 
         os.kill(self.pid, sig)
 
     def isalive(self):
-        '''Determine whether the child process is still running.
+        """Determine whether the child process is still running.
 
         Args:
             None.
 
         Returns:
             Boolean indicating whether process is alive.
-        '''
+        """
 
         if self.waited:
             return False
@@ -88,19 +88,19 @@
         return False
 
     def send(self, data):
-        '''Send data to the sub-process's stdin.
+        """Send data to the sub-process's stdin.
 
         Args:
             data: The data to send to the process.
 
         Returns:
             Nothing.
-        '''
+        """
 
         os.write(self.fd, data)
 
     def expect(self, patterns):
-        '''Wait for the sub-process to emit specific data.
+        """Wait for the sub-process to emit specific data.
 
         This function waits for the process to emit one pattern from the
         supplied list of patterns, or for a timeout to occur.
@@ -116,7 +116,7 @@
         Notable exceptions:
             Timeout, if the process did not emit any of the patterns within
             the expected time.
-        '''
+        """
 
         for pi in xrange(len(patterns)):
             if type(patterns[pi]) == type(''):
@@ -161,7 +161,7 @@
                 self.logfile_read.flush()
 
     def close(self):
-        '''Close the stdio connection to the sub-process.
+        """Close the stdio connection to the sub-process.
 
         This also waits a reasonable time for the sub-process to stop running.
 
@@ -170,7 +170,7 @@
 
         Returns:
             Nothing.
-        '''
+        """
 
         os.close(self.fd)
         for i in xrange(100):