[LTP] [PATCH] setegid01.c: Rewrite using new LTP API

[Petr Vorel]

Hi Avinesh,

thanks merged, with few small change:

* add the last check of result of SAFE_SETEGID(orig_egid) (was in the original):
	SAFE_GETRESGID(&cur_rgid, &cur_egid, &orig_sgid);
	TST_EXP_EQ_LU(orig_egid, cur_egid);

I also reword doc and TINFO messages a bit.

Kind regards,
Petr