Revert "OS-8005 bhyve memory pressure needs to target ARC better (#354)"
This reverts commit a6033573eedd94118d2b9e65f45deca0bf4b42f7.

*** 36,46 ****
   * A full copy of the text of the CDDL should have accompanied this
   * source.  A copy of the CDDL is also available via the Internet at
   * http://www.illumos.org/license/CDDL.
   *
   * Copyright 2015 Pluribus Networks Inc.
!  * Copyright 2020 Joyent, Inc.
   */
  
  #ifndef _VMM_DEV_H_
  #define _VMM_DEV_H_
  
--- 36,46 ----
   * A full copy of the text of the CDDL should have accompanied this
   * source.  A copy of the CDDL is also available via the Internet at
   * http://www.illumos.org/license/CDDL.
   *
   * Copyright 2015 Pluribus Networks Inc.
!  * Copyright 2019 Joyent, Inc.
   */
  
  #ifndef _VMM_DEV_H_
  #define _VMM_DEV_H_
  
*** 370,380 ****
  #define VM_GET_CPUS                     (VMM_IOC_BASE | 0x1c)
  #define VM_SUSPEND_CPU                  (VMM_IOC_BASE | 0x1d)
  #define VM_RESUME_CPU                   (VMM_IOC_BASE | 0x1e)
  
  #define VM_PPTDEV_DISABLE_MSIX          (VMM_IOC_BASE | 0x1f)
- #define VM_ARC_RESV                     (VMM_IOC_BASE | 0xfe)
  
  #define VM_DEVMEM_GETOFFSET             (VMM_IOC_BASE | 0xff)
  
  #define VMM_CTL_DEV             "/dev/vmmctl"
  
--- 370,379 ----