Mismatching declarations of revision strings in HiSax

The {l1,l2,l3,lli,tei}_revision strings in the HiSax driver are 'const',
but have a mismatching declaration as 'extern char *' in config.c.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/isdn/hisax/config.c

@@ -361,11 +361,11 @@ module_param_array(io1, int, NULL, 0);
 
 int nrcards;
 
-extern char *l1_revision;
-extern char *l2_revision;
-extern char *l3_revision;
-extern char *lli_revision;
-extern char *tei_revision;
+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;
 
 char *HiSax_getrev(const char *revision)
 {