net/hp100: fix section mismatch warning

Fix following section mismatch warning in hp100:

WARNING: drivers/net/hp100.o(.init.text+0x26a): Section mismatch: reference to .exit.text: (after 'init_module')

The warning says that we use a function marked __exit from a
function marked __init.
This is not good on architectures where we discard __exit section
for drivers that are built-in.

Note: This warning is only seen by my local copy of modpost
      but the change will soon hit upstream.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>