usr.sbin/sendmail: build warnings fixed

[aprieger_llnw.com]

Summary

usr.sbin/sendmail: warning fixes via edits to the C code files

[aprieger_llnw.com]

Changelog:

1. contrib/sendmail/src/envelope.c
   • Warnings
     • warning: format not a string literal and no format arguments [-Wformat-security]
   • Fixes:
     • Add the modifier "$s" to the "message( )" functions calls at line 221
2. contrib/sendmail/src/parseaddr.c
   • Warnings:
     • warning: format not a string literal and no format arguments [-Wformat-security]
   • Fixes:
     • Add the modifier "$s" to the "message( )" functions calls at lines 326 & 423
3. contrib/sendmail/src/srvrsmtp.c
   • Warnings:
     • warning: format not a string literal and no format arguments [-Wformat-security]
   • Fixes:
     • Add the modifier "$s" to the "usrerr( )" functions calls at lines 581, 587. 1852, 2455, 3662 & 3782
     • Add the modifier "$s" to the "message( )" functions calls at line 934