We can't rely on vmalloc.h being included by other included files because
under some configs it is possible for the build to fail:

drivers/misc/vmw_vmci/vmci_queue_pair.c: In function 'qp_free_queue':
drivers/misc/vmw_vmci/vmci_queue_pair.c:270: error: implicit declaration of function 'vunmap'
drivers/misc/vmw_vmci/vmci_queue_pair.c:277: error: implicit declaration of function 'vfree'
drivers/misc/vmw_vmci/vmci_queue_pair.c: In function 'qp_alloc_queue':
drivers/misc/vmw_vmci/vmci_queue_pair.c:302: error: implicit declaration of function 'vmalloc'
drivers/misc/vmw_vmci/vmci_queue_pair.c:302: warning: assignment makes pointer from integer without a cast
drivers/misc/vmw_vmci/vmci_queue_pair.c:324: error: implicit declaration of function 'vmap'
drivers/misc/vmw_vmci/vmci_queue_pair.c:324: error: 'VM_MAP' undeclared (first use in this function)
drivers/misc/vmw_vmci/vmci_queue_pair.c:324: error: (Each undeclared identifier is reported only once
drivers/misc/vmw_vmci/vmci_queue_pair.c:324: error: for each function it appears in.)
drivers/misc/vmw_vmci/vmci_queue_pair.c: In function 'qp_host_map_queues':
drivers/misc/vmw_vmci/vmci_queue_pair.c:843: error: 'VM_MAP' undeclared (first use in this function)

Fix the build by directly including vmalloc.h.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: George Zhang <georgezhang@vmware.com>
Cc: Andy King <acking@vmware.com>
Cc: Dmitry Torokhov <dtor@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>