Add Socket Libraries.

Add Posix functions for porting compatibility.
Fix compliance issues with ISO/IEC 9899:199409
New Functions:
  setenv(), fparseln(), GetFileNameFromPath(), rename(),
  realpath(), setprogname(), getprogname(), strlcat(), strlcpy(),
  strsep(), setitimer(), getitimer(), timegm(), getopt(), basename(),
  mkstemp(), ffs(), vsnprintf(), snprintf(), getpass(), usleep(), select(),
  writev(), strcasecmp(), getcwd(), chdir(), tcgetpgrp(), getpgrp(), gettimeofday(),
  bcopy(), 


git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12061 6f19259b-4bc3-4df7-8a09-765794883524

StdLib/Include/sys/stat.h

@@ -210,7 +210,7 @@ __BEGIN_DECLS
   extern int      fstat     (int, struct stat *);
   extern int      lstat     (const char *, struct stat *);
   extern int      stat      (const char *, void *);
-//  extern int      chmod     (const char *, mode_t);
+  extern int      chmod     (const char *, mode_t);
 #endif  // __STAT_SYSCALLS_DECLARED
 __END_DECLS