SWV: Software Video now compiles and runs on x64

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@4411 8ced0084-cf51-0410-be5f-012b33b47a6e

Source/Plugins/Plugin_VideoSoftware/Src/TextureSampler.cpp

@@ -30,11 +30,17 @@ inline int iround(float x)
 {
     int t;
 
-    __asm volatile
+#if defined(_WIN32) && !defined(_M_X64)
+    __asm
     {
         fld  x
         fistp t
     }
+#else
+	t = (int)x;
+	if((x - t) >= 0.5)
+		return t + 1;
+#endif
 
     return t;
 }