Tools: hv: remove unused bytes_written from kvp_update_file()

fwrite() does not actually return the number of bytes written and
this value is being ignored anyway and ferror() is being called to
check for an error. As we assign to this variable and never use it
we get the following compile-time warning:
hv_kvp_daemon.c:149:9: warning: variable .bytes_written. set but not used [-Wunused-but-set-variable]
Remove bytes_written completely.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tools/hv/hv_kvp_daemon.c

@@ -147,7 +147,6 @@ static void kvp_release_lock(int pool)
 static void kvp_update_file(int pool)
 {
 	FILE *filep;
-	size_t bytes_written;
 
 	/*
 	 * We are going to write our in-memory registry out to
@@ -163,8 +162,7 @@ static void kvp_update_file(int pool)
 		exit(EXIT_FAILURE);
 	}
 
-	bytes_written = fwrite(kvp_file_info[pool].records,
-				sizeof(struct kvp_record),
+	fwrite(kvp_file_info[pool].records, sizeof(struct kvp_record),
 				kvp_file_info[pool].num_records, filep);
 
 	if (ferror(filep) || fclose(filep)) {