ptp: Fix possible memory leak in ptp_clock_register()

mainline inclusion
from mainline-v5.15-rc7
commit 4225fea1
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9RBLZ
CVE: CVE-2021-47455

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=4225fea1cb28370086e17e82c0f69bec2779dca0



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I got memory leak as follows when doing fault injection test:

unreferenced object 0xffff88800906c618 (size 8):
  comm "i2c-idt82p33931", pid 4421, jiffies 4294948083 (age 13.188s)
  hex dump (first 8 bytes):
    70 74 70 30 00 00 00 00                          ptp0....
  backtrace:
    [<00000000312ed458>] __kmalloc_track_caller+0x19f/0x3a0
    [<0000000079f6e2ff>] kvasprintf+0xb5/0x150
    [<0000000026aae54f>] kvasprintf_const+0x60/0x190
    [<00000000f323a5f7>] kobject_set_name_vargs+0x56/0x150
    [<000000004e35abdd>] dev_set_name+0xc0/0x100
    [<00000000f20cfe25>] ptp_clock_register+0x9f4/0xd30 [ptp]
    [<000000008bb9f0de>] idt82p33_probe.cold+0x8b6/0x1561 [ptp_idt82p33]

When posix_clock_register() returns an error, the name allocated
in dev_set_name() will be leaked, the put_device() should be used
to give up the device reference, then the name will be freed in
kobject_cleanup() and other memory will be freed in ptp_clock_release().

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: a33121e5 ("ptp: fix the race between the release of ptp_clock and cdev")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
	drivers/ptp/ptp_clock.c
['ptp->vclock_index' is introduced since commit 44c494c8 ("ptp:
track available ptp vclocks information"), so drop the code
`kfree(ptp->vclock_index);`]
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>