ptp: add testptp mask test

ptp: add testptp mask test

[ Upstream commit 26285e689c6cd2cf3849568c83b2ebe53f467143 ]

Add option to test timestamp event queue mask manipulation in testptp.

Option -F allows the user to specify a single channel that will be
applied on the mask filter via IOCTL.

The test program will maintain the file open until user input is
received.

This allows checking the effect of the IOCTL in debugfs.

eg:

Console 1:
```
Channel 12 exclusively enabled. Check on debugfs.
Press any key to continue
```

Console 2:
```
0x00000000 0x00000001 0x00000000 0x00000000 0x00000000 0x00000000
0x00000000 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000
0x00000000 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000
0x00000000 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000
0x00000000 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000
0x00000000 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000
0x00000000 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000
0x00000000 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000
0x00000000 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000
0x00000000 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000
0x00000000 0x00000000 0x00000000 0x00000000
```

Signed-off-by: Xabier Marquiegui <reibax@gmail.com>
Suggested-by: Richard Cochran <richardcochran@gmail.com>
Suggested-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 76868642e427 ("testptp: Add option to open PHC in readonly mode")
Signed-off-by: Sasha Levin <sashal@kernel.org>