BugLink: https://bugs.launchpad.net/bugs/1836668

[ Upstream commit fbc318af ]

Gadget drivers may queue request in interrupt context. This would lead to
a descriptor allocation in that context. In that case we would hit
BUG_ON(in_interrupt()) in __get_vm_area_node.

Also remove the unnecessary cast.
Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com>
Tested-by: James Grant <jamesg@zaltys.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>