soc/fsl/qe: Fix an error code in qe_pin_request()

soc/fsl/qe: Fix an error code in qe_pin_request()

BugLink: https://bugs.launchpad.net/bugs/1863019
[ Upstream commit 5674a92ca4b7e5a6a19231edd10298d30324cd27 ]

We forgot to set "err" on this error path.

Fixes: 1a2d397a6eb5 ("gpio/powerpc: Eliminate duplication of of_get_named_gpio_flags()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>