This triggers a warning on a recent nightly, which in turn breaks CI due to
`#![deny(warnings)]` in libc-test/build.rs

adding PATH_MAX

use type c_int for _PARM_NAME_MAX and _PARM_PATH_MAX

defining uintptr_t = usize and intptr_t/ptrdiff_t = isize, and using uintptr_t to define size_t, and intptr_t to define ssize_t.

2. implement Debug for big size array
3. remove code related to epoll
4. use 'pub enum' for _Vx_semaphore

2. change armv7-wrs-vxworks to armv7-wrs-vxworks-eabihf
3. code cleanup

Define the C interface to vxWorks for x86, x86_64, ARM, ARM 64-bit, PowerPC, PowerPC SPE and PowerPC 64-bit.