[easytag] Avoid compiler warning in et_flac_read_func()

[David King <davidk src gnome org>]

commit 2d7791969d689038e36c81575facf8d7e0673d3f
Author: David King <amigadave amigadave com>
Date:   Tue Dec 23 21:15:37 2014 +0000

    Avoid compiler warning in et_flac_read_func()
    
    Cast a GFileInputStream to a GInputStream when passed as the first
    argument to g_input_stream_read().

 src/tags/flac_private.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/tags/flac_private.c b/src/tags/flac_private.c
index 0732ca3..16494a0 100644
--- a/src/tags/flac_private.c
+++ b/src/tags/flac_private.c
@@ -33,8 +33,8 @@ et_flac_read_func (void *ptr,
 
     state->eof = FALSE;
 
-    bytes_read = g_input_stream_read (state->istream, ptr, size * nmemb, NULL,
-                                      &state->error);
+    bytes_read = g_input_stream_read (G_INPUT_STREAM (state->istream), ptr,
+                                      size * nmemb, NULL, &state->error);
 
     if (bytes_read == -1)
     {