IDE: fix sparse signed-ness errors with host->host_busy

The host_busy field in struct ide_host defaults to a
signed-long, where most arch's test_and_set_bit_*
macros use an unsigned long.

Change to using an unsigned long, which on ARM removes
the following sparse errors:

drivers/ide/ide-io.c:681:8: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:681:8:    expected unsigned long volatile *p
drivers/ide/ide-io.c:681:8:    got long volatile *<noident>
drivers/ide/ide-io.c:681:8: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:681:8:    expected unsigned long volatile *p
drivers/ide/ide-io.c:681:8:    got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3:    expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3:    got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3:    expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3:    got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3:    expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3:    got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3:    expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3:    got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3:    expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3:    got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3:    expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3:    got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3:    expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3:    got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3:    expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3:    got long volatile *<noident>

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>