test_firmware: fix memory leak in test_firmware_init()

When misc_register() failed in test_firmware_init(), the memory pointed
by test_fw_config->name is not released. The memory leak information is
as follows:
unreferenced object 0xffff88810a34cb00 (size 32):
  comm "insmod", pid 7952, jiffies 4294948236 (age 49.060s)
  hex dump (first 32 bytes):
    74 65 73 74 2d 66 69 72 6d 77 61 72 65 2e 62 69  test-firmware.bi
    6e 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  n...............
  backtrace:
    [<ffffffff81b21fcb>] __kmalloc_node_track_caller+0x4b/0xc0
    [<ffffffff81affb96>] kstrndup+0x46/0xc0
    [<ffffffffa0403a49>] __test_firmware_config_init+0x29/0x380 [test_firmware]
    [<ffffffffa040f068>] 0xffffffffa040f068
    [<ffffffff81002c41>] do_one_initcall+0x141/0x780
    [<ffffffff816a72c3>] do_init_module+0x1c3/0x630
    [<ffffffff816adb9e>] load_module+0x623e/0x76a0
    [<ffffffff816af471>] __do_sys_finit_module+0x181/0x240
    [<ffffffff89978f99>] do_syscall_64+0x39/0xb0
    [<ffffffff89a0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: c92316bf8e ("test_firmware: add batched firmware tests")
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20221119035721.18268-1-shaozhengchao@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

lib/test_firmware.c

@@ -1491,6 +1491,7 @@ static int __init test_firmware_init(void)
 
 	rc = misc_register(&test_fw_misc_device);
 	if (rc) {
+		__test_firmware_config_free();
 		kfree(test_fw_config);
 		pr_err("could not register misc device: %d\n", rc);
 		return rc;