winedbg: Close filehandle on one exit branch (Coverity).

programs/winedbg/source.c

@@ -87,7 +87,10 @@ static  void*   source_map_file(const char* name, HANDLE* hMap, unsigned* size)
     hFile = CreateFileA(name, GENERIC_READ, FILE_SHARE_READ, NULL,
                         OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
     if (hFile == INVALID_HANDLE_VALUE) return (void*)-1;
-    if (size != NULL && (*size = GetFileSize(hFile, NULL)) == -1) return (void*)-1;
+    if (size != NULL && (*size = GetFileSize(hFile, NULL)) == INVALID_FILE_SIZE) {
+        CloseHandle(hFile);
+        return (void*)-1;
+    }
     *hMap = CreateFileMappingW(hFile, NULL, PAGE_READONLY, 0, 0, NULL);
     CloseHandle(hFile);
     if (!*hMap) return (void*)-1;