coverity#1202907 Uninitialized scalar variable

Change-Id: I7c33a9ecaec6a771fa2a22c0ddb38a0a9b1d2df7

vcl/source/filter/sgvmain.cxx

@@ -260,6 +260,7 @@ SvStream& ReadTextType(SvStream& rInp, TextType& rText)
 }
 SvStream& ReadBmapType(SvStream& rInp, BmapType& rBmap)
 {
+    memset((char*)&rBmap.Last, 0, BmapSize);
     rInp.Read((char*)&rBmap.Last,BmapSize);
 #if defined OSL_BIGENDIAN
     SWAPOBJK (rBmap);