Defines starting with `p' in vm

• PAGER_MAP_SIZE vm/vm_pager.c:110
• PAGE_SHIFT vm/vm_param.h:97
• PAGE_SIZE vm/vm_param.h:96
• PG_DEVICE vm/vm_pager.h:62
• PG_DFLT vm/vm_pager.h:59
• PG_SWAP vm/vm_pager.h:60
• PG_VNODE vm/vm_pager.h:61
• _PMAP_VM_ vm/pmap.h:71