fix chmod error message

[cgzones]

Macro was defined twice

btw.: should every systemcall failure be reported with the suffix: which returned [(%d)-(%s)]." errno, strerror(errno)?

[jrossi]

@cgzones makes sense and would make DEBUGing weird problem simpler.

[awiddersheim]

I like that idea. Just haven't had the time to go through and implement that everywhere.

[awiddersheim]

I'd merge this but the spacing is a bit weird between the errno and sterror() parameters:

ErrorExit(CHMOD_ERROR, ARGV0, AUTH_FILE, errno ,strerror(errno))