Avoid shadowing in fdwalk

-Wshadow=local caught this buglet.  fdwalk redeclares "result" in the
inner scope, meaning that this function will always return 0, even on
error.

gdb/ChangeLog
2018-10-04  Tom Tromey  <tom@tromey.com>

	* common/filestuff.c (fdwalk): Remove inner declaration of
	"result".

gdb/ChangeLog

@@ -1,3 +1,8 @@
+2018-10-04  Tom Tromey  <tom@tromey.com>
+
+	* common/filestuff.c (fdwalk): Remove inner declaration of
+	"result".
+
 2018-10-04  Tom Tromey  <tom@tromey.com>
 
 	* msp430-tdep.c (msp430_push_dummy_call): Rename inner

gdb/common/filestuff.c

@@ -80,7 +80,6 @@ fdwalk (int (*func) (void *, int), void *arg)
 	{
 	  long fd;
 	  char *tail;
-	  int result;
 
 	  errno = 0;
 	  fd = strtol (entry->d_name, &tail, 10);