windows: Rename free_windows to windows_free

Change-Id: Ifd9edb499069b6b7df48155aa2c8e955426751a5
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
diff --git a/windows.h b/windows.h
index a1901c2..002e507 100644
--- a/windows.h
+++ b/windows.h
@@ -11,7 +11,7 @@
 
 /* Initialisation Functions */
 int windows_init(struct mbox_context *context);
-void free_windows(struct mbox_context *context);
+void windows_free(struct mbox_context *context);
 /* Write From Window Functions */
 int write_from_window_v1(struct mbox_context *context,
 			 uint32_t offset_bytes, uint32_t count_bytes);