Remove inclusion of netinet/ip_compat.h for FreeBSD. This header is not

always available, and nothing in sanitizer_platform_limits_posix.cc uses
any of its definitions.

See also: https://svnweb.freebsd.org/changeset/base/277201

Reviewers: kcc, kutuzov.viktor.84, samsonov
Reviewed By: samsonov
Differential Revision: http://reviews.llvm.org/D7486

llvm-svn: 229518