drivers/isdn/hisax: fix sparse warning: Should it be static?

Impact: Move declarations to a header file.

Fix this sparse warning:
  drivers/isdn/hisax/callc.c:24:12: warning: symbol 'lli_revision' was not declared. Should it be static?
  drivers/isdn/hisax/config.c:84:12: warning: symbol 'CardType' was not declared. Should it be static?
  drivers/isdn/hisax/config.c:362:5: warning: symbol 'nrcards' was not declared. Should it be static?
  drivers/isdn/hisax/isdnl1.c:21:12: warning: symbol 'l1_revision' was not declared. Should it be static?
  drivers/isdn/hisax/isdnl2.c:22:12: warning: symbol 'l2_revision' was not declared. Should it be static?
  drivers/isdn/hisax/isdnl3.c:22:12: warning: symbol 'l3_revision' was not declared. Should it be static?
  drivers/isdn/hisax/tei.c:23:12: warning: symbol 'tei_revision' was not declared. Should it be static?

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/isdn/hisax/hisax.h b/drivers/isdn/hisax/hisax.h
index e8d429f..f852704 100644
--- a/drivers/isdn/hisax/hisax.h
+++ b/drivers/isdn/hisax/hisax.h
@@ -121,6 +121,15 @@
 
 #ifdef __KERNEL__
 
+extern const char *CardType[];
+extern int nrcards;
+
+extern const char *l1_revision;
+extern const char *l2_revision;
+extern const char *l3_revision;
+extern const char *lli_revision;
+extern const char *tei_revision;
+
 /* include l3dss1 & ni1 specific process structures, but no other defines */
 #ifdef CONFIG_HISAX_EURO
   #define l3dss1_process