[PATCH] IPC: add PATH_MAX-less fallback definition for MAX_PATH

[PATCH] IPC: add PATH_MAX-less fallback definition for MAX_PATH

Define MAX_PATH also when PATH_MAX is not defined (e.g on GNU/Hurd).
MAX_PATH is Windows constant, and it is used in this file only in a
code path for Windows; because of this, the static fallback define
should be good enough.

Change-Id: Ic1b9fee3b62505f86aa8ec89bbd20493bfe1f67c
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Gbp-Pq: Name upstream_IPC-add-PATH_MAX-less-fallback-definition-for-MAX_PA.patch