tests: (lsfd) normalize protoname before comparing

tests: (lsfd) normalize protoname before comparing

This is a follow-up commit to a60ac11fe0087584f37329b4733edfade3452c64.

>    In the commit, the protoname of (AF_UNIX, SOCK_DGRAM) sockets was also
>    changed to "UNIX-DGRAM". However, it was renamed back to "UNIX" in
>    https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0edf0824e0dc359ed76bf96af986e6570ca2c0b9

To make this test case more portable, this change makes the test case
accept "UINX-DGRAM" in addition to "UINX", too.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>