msdmo: Remove superfluous pointer casts.

dlls/msdmo/dmoreg.c

diff --git a/dlls/msdmo/dmoreg.c b/dlls/msdmo/dmoreg.c
index 97388c9..a3dc930 100644
--- a/dlls/msdmo/dmoreg.c
+++ b/dlls/msdmo/dmoreg.c
@@ -450,11 +450,11 @@
     if(IsEqualIID(riid, &IID_IUnknown))
         *ppvObj = This;
     else if(IsEqualIID(riid, &IID_IEnumDMO))
-        *ppvObj = (IEnumDMO*)This;
+        *ppvObj = This;
 
     if(*ppvObj)
     {
-        IEnumDMO_fnAddRef((IEnumDMO*)*ppvObj);
+        IEnumDMO_fnAddRef(*ppvObj);
         return S_OK;
     }