wifi: ath11k: Fix memory leak in ath11k_peer_rx_frag_setup

crypto_alloc_shash() allocates resources, which should be released by
crypto_free_shash(). When ath11k_peer_find() fails, there has memory
leak. Add missing crypto_free_shash() to fix this.

Fixes: 243874c6 ("ath11k: handle RX fragments")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20230102081142.3937570-1-linmq006@gmail.com