net: cosmetic: Clean up NFS variables and functions

Make a thorough pass through all variables and function names contained
within nfs.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/net.c b/net/net.c
index f740052..bb67884 100644
--- a/net/net.c
+++ b/net/net.c
@@ -235,7 +235,7 @@
 		/*
 		 * Use NFS to load the bootfile.
 		 */
-		NfsStart();
+		nfs_start();
 		return;
 	}
 #endif
@@ -407,7 +407,7 @@
 #endif
 #if defined(CONFIG_CMD_NFS)
 		case NFS:
-			NfsStart();
+			nfs_start();
 			break;
 #endif
 #if defined(CONFIG_CMD_CDP)