[libsoup] Add missing prototype

[Ignacio Casal Quinteiro <icq src gnome org>]

commit a185ec2543034d7eaae5e18e2f87a3ecbc02297b
Author: Ignacio Casal Quinteiro <icq gnome org>
Date:   Tue Oct 13 12:14:13 2015 +0200

    Add missing prototype
    
    This is needed for mingw

 libsoup/soup-init.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/libsoup/soup-init.c b/libsoup/soup-init.c
index 92eb837..c4950ce 100644
--- a/libsoup/soup-init.c
+++ b/libsoup/soup-init.c
@@ -38,6 +38,10 @@ soup_init (void)
 
 #if defined (G_OS_WIN32)
 
+BOOL WINAPI DllMain (HINSTANCE hinstDLL,
+                     DWORD     fdwReason,
+                     LPVOID    lpvReserved);
+
 BOOL WINAPI
 DllMain (HINSTANCE hinstDLL,
          DWORD     fdwReason,