ltp: remove patches that already have fixes upstream

ltp: remove patches that already have fixes upstream

The following patches has already fixes for the issues they are solving
in upstream.
- 0001-add-_GNU_SOURCE-to-pec_listener.c.patch
- 0011-Rename-sigset-variable-to-sigset1.patch
- 0025-mc_gethost-include-sys-types.h.patch
- 0027-sysconf01-Use-_SC_2_C_VERSION-conditionally.patch
- 0033-shmat1-Cover-GNU-specific-code-under-__USE_GNU.patch

Suggested-by: Yi Zhao <yi.zhao@windriver.com>
(From OE-Core rev: 88e12a14540e10718fb2e68f27834d9b7565ab7e)

Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>