watchdog: hpwdt: Fix initialization message in hpwdt.c

allow_kdump was enabled as default since following commit.

commit a089361c,
watchdog: hpwdt: Unregister NMI events on exit.

But the initialization message was not modified.
So it still shows

  HP Watchdog Timer Driver: NMI decoding initialized,
  allow kernel dump: ON (default = 0/OFF)    <=

This "default = 0/OFF" message may confuse users.
Fix it as "default = 1/ON".

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>