fix tube's debug output of same byte compression

[tkmikan]

The tube will compress same byte in debug output, however it prints data[0], which is int.
And send still prints * 0x1, while recv omits it.

from pwn import *
context.log_level = 'debug'

t = tube()
t.recv_raw = lambda n: b'a'
t.recv()
t.recv_raw = lambda n: b'a' * 4
t.recv()
t.send_raw = lambda x: None
t.send(b'a')
t.send(b'aaaa')

before pr:

[DEBUG] Received 0x1 bytes:
    b'a'
[DEBUG] Received 0x4 bytes:
    97 * 0x4
[DEBUG] Sent 0x1 bytes:
    97 * 0x1
[DEBUG] Sent 0x4 bytes:
    97 * 0x4

after pr:

[DEBUG] Received 0x1 bytes:
    b'a'
[DEBUG] Received 0x4 bytes:
    b'a' * 0x4
[DEBUG] Sent 0x1 bytes:
    b'a'
[DEBUG] Sent 0x4 bytes:
    b'a' * 0x4

[tkmikan]

One more thing: previously when recv a single unprintable byte, its hexdump is printed, while compression never print hexdump (now send behaves the same).
My question is, is hexdumping single byte necessary?

[Arusekk]

Wow, I was annoyed by it too, but was unaware that it was not intended. This exposes some code duplication we have here. Could this logic be moved to a new function, say, maybe_hexdump?