[LTP] [PATCH 2/3] syscalls/fchmod01.c: Convert to new API && merge fchmod07 into fchmod01

[Petr Vorel]

Hi Jinhui,

Pushed, thanks!
I just use SPDX-License-Identifier: GPL-2.0-or-later
removed 3 unused headers and changed array modes to lower case.

Kind regards,
Petr