avdevice/decklink_common: fix COM initialization failure check

Signed-off-by: Jonathan Baecker <jonbae77@gmail.com>
Reviewed-by: Ramiro Polla <ramiro.polla@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavdevice/decklink_common.cpp

@@ -42,7 +42,7 @@ IDeckLinkIterator *CreateDeckLinkIteratorInstance(void)
 {
     IDeckLinkIterator *iter;
 
-    if (CoInitialize(NULL) != S_OK) {
+    if (CoInitialize(NULL) < 0) {
         av_log(NULL, AV_LOG_ERROR, "COM initialization failed.\n");
         return NULL;
     }