Remove check of eof() return value validity.

It's useless and resulted in a warning from Coverity as it correctly
determined that this code could never be executed under Unix.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@73138 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/file.cpp

@@ -511,10 +511,6 @@ bool wxFile::Eof() const
     {
         wxLogSysError(_("can't determine if the end of file is reached on descriptor %d"), m_fd);
     }
-    else if ( iRc != 1 )
-    {
-        wxFAIL_MSG(wxT("invalid eof() return value."));
-    }
 
     return true;
 }