drm/i915/dmc: Fix extra bracket and wrong variable in PIPEDMC error logs

drm/i915/dmc: Fix extra bracket and wrong variable in PIPEDMC error logs

Fixes two issues in intel_pipedmc_irq_handler():
- Removed an extra ']' in the PIPEDMC error and interrupt vector log.
- Corrected the interrupt vector log to print int_vector instead of tmp,
  as tmp will be zero in this case.

Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patch.msgid.link/20251103132337.762156-1-alok.a.tiwari@oracle.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>