shill: Elevates raw netlink attributes to fully-fledged attributes.

This CL contains several small modifications to get and set raw
attributes like the other attributes and removes back doors used by
code to parse raw attribute data outside of the NetlinkAttribute
mechanism.  As part of this, netlink attribute headers have been removed
from the raw attribute data.

BUG=None.
TEST=unittests

Change-Id: I201ce7ffbc85558ae97a492921c3f5f4bfc4d0d4
Reviewed-on: https://gerrit.chromium.org/gerrit/44185
Commit-Queue: Wade Guthrie <wdg@chromium.org>
Reviewed-by: Wade Guthrie <wdg@chromium.org>
Tested-by: Wade Guthrie <wdg@chromium.org>
diff --git a/nl80211_message.cc b/nl80211_message.cc
index e49f65e..34381e0 100644
--- a/nl80211_message.cc
+++ b/nl80211_message.cc
@@ -70,7 +70,7 @@
     LAZY_INSTANCE_INITIALIZER;
 }  // namespace
 
-const char Nl80211Message::kBogusMacAddress[]="XX:XX:XX:XX:XX:XX";
+const char Nl80211Message::kBogusMacAddress[] = "XX:XX:XX:XX:XX:XX";
 
 const uint8_t Nl80211Frame::kMinimumFrameByteCount = 26;
 const uint8_t Nl80211Frame::kFrameTypeMask = 0xfc;