vm_allocate_contiguous: Add missing page unwiring after making the area non-pageableHEADmaster

Otherwise, if the allocated memory is passed over for returning data such as
in device_read, we end up with

../vm/vm_map.c:4245: vm_map_copyin_page_list: Assertion `src_entry->wired_count > 0' failed.Debugger invoked: assertion failure

1 files changed, 3 insertions, 0 deletions

diff --git a/vm/vm_user.c b/vm/vm_user.c
index 868230a3..62aedad3 100644
--- a/vm/vm_user.c
+++ b/vm/vm_user.c
@@ -692,6 +692,9 @@ kern_return_t vm_allocate_contiguous(
 		return kr;
 	}
 
+	for (i = 0; i < vm_page_atop(size); i++)
+		vm_page_unwire(&pages[i]);
+
 	*result_vaddr = vaddr;
 	*result_paddr = pages->phys_addr;