drm/panfrost: Add missing OPP table refcnt decremental

Commit f11b0417 ("drm/panfrost: Add fdinfo support GPU load metrics")
retrieves the OPP for the maximum device clock frequency, but forgets to
keep the reference count balanced by putting the returned OPP object. This
eventually leads to an OPP core warning when removing the device.

Fix it by putting OPP objects as many times as they're retrieved.

Also remove an unnecessary whitespace.

Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
Fixes: f11b0417 ("drm/panfrost: Add fdinfo support GPU load metrics")
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241105205458.1318989-1-adrian.larumbe@collabora.com