net: cosmetic: Clean up CDP variables and functions

Make a thorough pass through all variables and function names contained
within cdp.c and remove CamelCase and improve naming.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/net/cdp.h b/net/cdp.h
index 95e4ce0..83475c9 100644
--- a/net/cdp.h
+++ b/net/cdp.h
@@ -14,7 +14,7 @@
 #ifndef __CDP_H__
 #define __CDP_H__
 
-void CDPStart(void);
+void cdp_start(void);
 /* Process a received CDP packet */
 void cdp_receive(const uchar *pkt, unsigned len);