Fixed PR15456 by updating syscall tapsets with compat function changes.

Fixed PR15456 by updating syscall tapsets with compat function changes.

* tapset/linux/syscalls.stp (syscall.compat_sys_msgrcv): Updated for newer
  kernel compat function argument names.
  (syscall.compat_sys_msgsnd): Ditto.
* tapset/linux/syscalls2.stp (syscall.compat_sys_semctl): Updated for
  newer kernel compat function argument names.
  (syscall.compat_sys_shmat): Updated for newer kernel compat function
  argument names. Deprecated old "first", "second", "third" variable names
  in favor of variable names that match the non-compat probe alias.
* tapset/linux/nd_syscalls2.stp: Ditto.
* testsuite/buildok/nd_syscalls2-detailed.stp: Updated with new variables
  in the "shmat" probe alias.
* testsuite/buildok/syscalls2-detailed.stp: Ditto.
* NEWS: Mentioned variable deprecations.