[librsvg] Remove unused prototype

[Federico Mena Quintero <federico src gnome org>]

commit b74a3dcf10298d9836d94ade5a947f1cacbf5b13
Author: Federico Mena Quintero <federico gnome org>
Date:   Tue Nov 27 09:59:30 2018 -0600

    Remove unused prototype

 rsvg_internals/src/handle.rs | 6 ------
 1 file changed, 6 deletions(-)
---
diff --git a/rsvg_internals/src/handle.rs b/rsvg_internals/src/handle.rs
index 8246013b..983897c1 100644
--- a/rsvg_internals/src/handle.rs
+++ b/rsvg_internals/src/handle.rs
@@ -44,12 +44,6 @@ extern "C" {
         href: *const libc::c_char,
     ) -> *const RsvgHandle;
 
-    fn _rsvg_handle_acquire_stream(
-        handle: *mut RsvgHandle,
-        href: *const libc::c_char,
-        error: *mut *mut glib_sys::GError,
-    ) -> *mut gio_sys::GInputStream;
-
     fn rsvg_handle_keep_image_data(handle: *const RsvgHandle) -> glib_sys::gboolean;
 
     fn rsvg_load_handle_xml_xinclude(