parisc: Drop the HP-UX ENOSYM and EREMOTERELEASE error codes
Those return codes are only defined for the parisc architecture and
are leftovers from when we wanted to be HP-UX compatible.
They are not returned by any Linux kernel syscall but do trigger
problems with the glibc strerrorname_np() and strerror() functions as
reported in glibc issue #31080.
There is no need to keep them, so simply remove them.