[MSVIDC32] Keep using CRAM_MAGIC for info structure validation (reactos#6498)

CRAM_MAGIC is being used to validate the info context structure contents
when the driver routines are being called, so partially revert 8be9121.

Just report "MSVC" as the main FourCC handler in CRAM_GetInfo() instead.

CORE-19453 CORE-15382

Author: katahiromz

dll/win32/msvidc32/msvideo1.c

@@ -538,7 +538,11 @@ static LRESULT CRAM_GetInfo( const Msvideo1Context *info, ICINFO *icinfo, DWORD
 
     icinfo->dwSize = sizeof(ICINFO);
     icinfo->fccType = ICTYPE_VIDEO;
+#ifdef __REACTOS__
+    icinfo->fccHandler = MSVC_MAGIC;
+#else
     icinfo->fccHandler = info ? info->dwMagic : CRAM_MAGIC;
+#endif
     icinfo->dwFlags = 0;
     icinfo->dwVersion = ICVERSION;
     icinfo->dwVersionICM = ICVERSION;
@@ -583,11 +587,7 @@ LRESULT WINAPI CRAM_DriverProc( DWORD_PTR dwDriverId, HDRVR hdrvr, UINT msg,
         if( info )
         {
             memset( info, 0, sizeof *info );
-#ifdef __REACTOS__
-            info->dwMagic = MSVC_MAGIC;
-#else
             info->dwMagic = CRAM_MAGIC;
-#endif
         }
         r = (LRESULT) info;
         break;