ISDN b1pcmcia.c: remove an unused variable

I'm getting the following compile warning in recent 2.6 kernels:

<-- snip -->

...
CC drivers/isdn/hardware/avm/b1pcmcia.o
drivers/isdn/hardware/avm/b1pcmcia.c: In function `b1pcmcia_init':
drivers/isdn/hardware/avm/b1pcmcia.c:203: warning: unused variable `err'
...

<-- snip -->

Since this variable is completely unused, the fix is simple:

@@ -200,7 +200,6 @@
 {
 	char *p;
 	char rev[32];
-	int err;
 
 	if ((p = strchr(revision, ':')) != 0 && p[1]) {
 		strlcpy(rev, p + 2, 32);