kernel: make the default config a default parameter

Currently you configure a kernel using the kernel config method.
This allows you to supply a base config file.  If this file is ''
then a defconfig is generated and used.  This leads to the following
construction:

	testkernel = job.kernel('2.6.18')
	testkernel.config('')

It seems senseless to mandate the parameter and yet take '' as
meaning default.  This patch makes this parameter default to ''.
Allowing the following:

	testkernel = job.kernel('2.6.18')
	testkernel.config()

Signed-off-by: Andy Whitcroft <apw@shadowen.org>



git-svn-id: http://test.kernel.org/svn/autotest/trunk@418 592f7852-d20e-0410-864c-8624ca9c26a4
diff --git a/client/bin/kernel.py b/client/bin/kernel.py
index 33b0317..7182536 100755
--- a/client/bin/kernel.py
+++ b/client/bin/kernel.py
@@ -109,7 +109,7 @@
 		# self.job.stdout.restore()
 
 
-	def config(self, config_file, config_list = None):
+	def config(self, config_file = '', config_list = None):
 		self.job.stdout.redirect(os.path.join(self.log_dir, 'stdout'))
 		config = kernel_config.kernel_config(self.job, self.build_dir, self.config_dir, config_file, config_list)
 		self.job.stdout.restore()