Add preprocessor directives not to try
to redefine sys_errlist[] or sys_nerr
There are already definitions:
extern __const char *__const sys_errlist[];
extern __const int sys_nerr;
in <stdio.h>
Actually we should have something like
NeedSysErrlist in imake definitions
to get rid of those #ifdefs.
Added proper SharedDtSvcReqs in lnxLib.tmpl and CplusplusLibC in
linux.cf. This allows the libstdc++ dependancy to be properly
declared for libDtSvc so that it is not neccessary to hardcode 'CCLINK
= g++' in the Imakefiles of programs linking angainst libDtSvc.