wifi: mt76: mt7921: fix resource leak in probe error path

wifi: mt76: mt7921: fix resource leak in probe error path

When pcim_iomap_region() or devm_kmemdup() fail, the code returns
directly without cleaning up previously allocated resources:
  - mt76_device allocated by mt76_alloc_device()
  - pci irq vectors allocated by pci_alloc_irq_vectors()
Fix this by jumping to the existing error cleanup path instead of
returning directly.

Fixes: ee5bb35d2b83 ("wifi: mt76: mt7921: Replace deprecated PCI function")
Fixes: 222606f43b58 ("wifi: mt76: mt7921: handle MT7902 irq_map quirk with mutable copy")
Signed-off-by: Hongling Zeng <zenghongling@kylinos.cn>
Link: https://patch.msgid.link/20260512065245.46496-1-zenghongling@kylinos.cn
Signed-off-by: Felix Fietkau <nbd@nbd.name>