i3c: master: svc: Recycle unused IBI slot

i3c: master: svc: Recycle unused IBI slot

In svc_i3c_master_handle_ibi(), an IBI slot is fetched from the pool
to store the IBI payload. However, when an error condition is encountered,
the function returns without recycling the IBI slot, resulting in an IBI
slot leak.

Fixes: c85e209b799f ("i3c: master: svc: fix ibi may not return mandatory data byte")
Signed-off-by: Stanley Chu <yschu@nuvoton.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20250829012309.3562585-3-yschu@nuvoton.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>