[PATCH] -Wundef fixes (hisax)

CARD_... in hisax are all used with #if; CARD_FN_ENTERNOW_PCI lacks define
to 0 if corresponding config option is not set.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/isdn/hisax/hisax.h

@@ -1241,6 +1241,8 @@ struct IsdnCardState {
 
 #ifdef CONFIG_HISAX_ENTERNOW_PCI
 #define CARD_FN_ENTERNOW_PCI 1
+#else
+#define CARD_FN_ENTERNOW_PCI 0
 #endif
 
 #define TEI_PER_CARD 1