firmware: arm_ffa: Unmap Rx/Tx buffers on init failure

ffa_init() maps the Rx/Tx buffers via ffa_rxtx_map() but on the
partition setup failure path it never unmaps them.

Add the missing ffa_rxtx_unmap() call in the error path so that
the Rx/Tx buffers are properly released before freeing the backing
pages.

Signed-off-by: Haoxiang Li <lihaoxiang@isrc.iscas.ac.cn>
Message-Id: <20251210031656.56194-1-lihaoxiang@isrc.iscas.ac.cn>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

Author: Haoxiang Li

drivers/firmware/arm_ffa/driver.c

@@ -2068,6 +2068,7 @@ static int __init ffa_init(void)
 
 	pr_err("failed to setup partitions\n");
 	ffa_notifications_cleanup();
+	ffa_rxtx_unmap(drv_info->vm_id);
 free_pages:
 	if (drv_info->tx_buffer)
 		free_pages_exact(drv_info->tx_buffer, rxtx_bufsz);