Classify methods in FAFTClient

There are too many methods in FAFTClient, so this CL is to classify them into
several groups: ec, bios, kernel. Methods which can be put into one of the
target group should be renamed with format _[group name]_[method name].
For example, dump_firmware should be modified to bios_dump. To call methods in
FAFTClient, use [group name].[method name].

BUG=chromium-os:36429
TEST=run firmware update tests

Change-Id: I7ead01246121b454c0a9f29e10bd026a77925e4f
Reviewed-on: https://gerrit.chromium.org/gerrit/38186
Reviewed-by: Tom Wai-Hong Tam <waihong@chromium.org>
Commit-Ready: Chun-Ting Chang <ctchang@chromium.org>
Tested-by: Chun-Ting Chang <ctchang@chromium.org>
diff --git a/server/cros/servo_test.py b/server/cros/servo_test.py
index 1793b40..82f6bb7 100644
--- a/server/cros/servo_test.py
+++ b/server/cros/servo_test.py
@@ -63,7 +63,7 @@
             'remote_log_file': '/tmp/faft_client.log',
             'remote_process': None,
             'ssh_tunnel': None,
-            'polling_rpc': 'is_available',
+            'polling_rpc': 'system.is_available',
             'ssh_config': '-o StrictHostKeyChecking=no '
                           '-o UserKnownHostsFile=/dev/null ',
         },