Remove a few more code parts which are unused on Linux

This change is abapted from Dmitry's changes to remove support for
non-Linux architectures.

* Makefile.am: Remove if LINUX/endif pairs.
* defs.h: Remove stream_ioctl() declaration.
* ioctl.c (ioctl_decode): Remove 'ifdef HAVE_SYS_STREAM_H' block.
* resource.c: Use 'defined(FOO)' instead of 'defined FOO' form.
* util.c: Likewise.
* signal.c: Remove conditional includes which are never used on Linux.
* stream.c: Likewise.
* file.c: Remove excessive empty lines.

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/defs.h b/defs.h
index e7e1ebb..67cd5c3 100644
--- a/defs.h
+++ b/defs.h
@@ -64,8 +64,7 @@
 
 /* Maximum number of args to a syscall.
  *
- * Make sure that all entries in all syscallent.h files
- * have nargs <= MAX_ARGS!
+ * Make sure that all entries in all syscallent.h files have nargs <= MAX_ARGS!
  * linux/<ARCH>/syscallent.h: all have nargs <= 6.
  */
 #ifndef MAX_ARGS
@@ -539,7 +538,6 @@
 extern int term_ioctl(struct tcb *, long, long);
 extern int sock_ioctl(struct tcb *, long, long);
 extern int proc_ioctl(struct tcb *, int, int);
-extern int stream_ioctl(struct tcb *, int, int);
 extern int rtc_ioctl(struct tcb *, long, long);
 extern int scsi_ioctl(struct tcb *, long, long);
 extern int block_ioctl(struct tcb *, long, long);