Fix build with old kernel headers

* strace.c (print_debug_info, maybe_allocate_tcb, print_signalled,
print_exited): Remove "const" qualifier from status variable to
workaround some old implementations of WIFSIGNALED/WIFSTOPPED/WIFEXITED
macros.
* v4l2.c: Include <linux/types.h>.
(v4l2_ioctl): Check that V4L2_CTRL_FLAG_NEXT_CTRL and VIDIOC_S_EXT_CTRLS
macros are defined.
* tests/Makefile.am (AM_CPPFLAGS): Define.
diff --git a/strace.c b/strace.c
index f851c98..0e131a1 100644
--- a/strace.c
+++ b/strace.c
@@ -2030,7 +2030,7 @@
 }
 
 static void
-print_debug_info(const int pid, const int status)
+print_debug_info(const int pid, int status)
 {
 	const unsigned int event = (unsigned int) status >> 16;
 	char buf[sizeof("WIFEXITED,exitcode=%u") + sizeof(int)*3 /*paranoia:*/ + 16];
@@ -2077,7 +2077,7 @@
 }
 
 static struct tcb *
-maybe_allocate_tcb(const int pid, const int status)
+maybe_allocate_tcb(const int pid, int status)
 {
 	if (!WIFSTOPPED(status)) {
 		if (detach_on_execve && pid == strace_child) {
@@ -2160,7 +2160,7 @@
 }
 
 static void
-print_signalled(struct tcb *tcp, const int pid, const int status)
+print_signalled(struct tcb *tcp, const int pid, int status)
 {
 	if (pid == strace_child) {
 		exit_code = 0x100 | WTERMSIG(status);
@@ -2184,7 +2184,7 @@
 }
 
 static void
-print_exited(struct tcb *tcp, const int pid, const int status)
+print_exited(struct tcb *tcp, const int pid, int status)
 {
 	if (pid == strace_child) {
 		exit_code = WEXITSTATUS(status);
diff --git a/tests/Makefile.am b/tests/Makefile.am
index e5899de..08d7a4d 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -1,6 +1,10 @@
 # Automake input for strace tests.
 
 AM_CFLAGS = $(WARN_CFLAGS)
+AM_CPPFLAGS = -I$(top_builddir)/$(OS)/$(ARCH) \
+	      -I$(top_srcdir)/$(OS)/$(ARCH) \
+	      -I$(top_builddir)/$(OS) \
+	      -I$(top_srcdir)/$(OS)
 
 check_PROGRAMS = \
 	caps \
diff --git a/v4l2.c b/v4l2.c
index c4541d9..69ff618 100644
--- a/v4l2.c
+++ b/v4l2.c
@@ -31,6 +31,7 @@
 
 #include <stdint.h>
 #include <sys/ioctl.h>
+#include <linux/types.h>
 #include <linux/videodev2.h>
 /* some historical constants */
 #ifndef V4L2_CID_HCENTER
@@ -353,11 +354,13 @@
 		if (entering(tcp)
 		    || (exiting(tcp) && tcp->auxstr && !syserror(tcp))) {
 			tprints(exiting(tcp) ? " => " : ", {id=");
+#ifdef V4L2_CTRL_FLAG_NEXT_CTRL
 			tcp->auxstr = (c.id & V4L2_CTRL_FLAG_NEXT_CTRL) ? "" : NULL;
 			if (tcp->auxstr) {
 				tprints("V4L2_CTRL_FLAG_NEXT_CTRL|");
 				c.id &= ~V4L2_CTRL_FLAG_NEXT_CTRL;
 			}
+#endif
 			printxval(v4l2_control_ids, c.id, "V4L2_CID_???");
 		}
 		if (exiting(tcp)) {
@@ -395,6 +398,7 @@
 		return 1;
 	}
 
+#ifdef VIDIOC_S_EXT_CTRLS
 	case VIDIOC_S_EXT_CTRLS:
 	case VIDIOC_TRY_EXT_CTRLS:
 	case VIDIOC_G_EXT_CTRLS: {
@@ -431,7 +435,7 @@
 			}
 			tprints("{id=");
 			printxval(v4l2_control_ids, ctrl.id, "V4L2_CID_???");
-#if HAVE_DECL_V4L2_CTRL_TYPE_STRING
+# if HAVE_DECL_V4L2_CTRL_TYPE_STRING
 			tprintf(", size=%u", ctrl.size);
 			if (ctrl.size > 0) {
 				if (must_print_values) {
@@ -439,7 +443,7 @@
 					printstr(tcp, (long) ctrl.string, ctrl.size);
 				}
 			} else
-#endif
+# endif
 			{
 				if (must_print_values) {
 					tprintf(", value=%i, value64=%lli", ctrl.value,
@@ -451,6 +455,7 @@
 		tprints("]}");
 		return 1;
 	}
+#endif /* VIDIOC_S_EXT_CTRLS */
 
 	case VIDIOC_ENUMSTD: {
 		struct v4l2_standard s;