build: Fix two compile errors during out-of-tree build
The first:
```
iptables/extensions/libebt_limit.c:21:26: fatal error: iptables/nft.h: No such file or directory
#include "iptables/nft.h"
```
The second:
```
/data/keno/sandbox/iptables/iptables/xtables-config-parser.y:19:32: fatal error: libiptc/linux_list.h: No such file or directory
#include <libiptc/linux_list.h>
^
```
Simply fixed by adding the relevant `-I` directives.
Signed-off-by: Keno Fischer <keno@juliacomputing.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/extensions/GNUmakefile.in b/extensions/GNUmakefile.in
index 33b06ef..b7a8a83 100644
--- a/extensions/GNUmakefile.in
+++ b/extensions/GNUmakefile.in
@@ -22,7 +22,7 @@
kinclude_CPPFLAGS = @kinclude_CPPFLAGS@
AM_CFLAGS = ${regular_CFLAGS}
-AM_CPPFLAGS = ${regular_CPPFLAGS} -I${top_builddir}/include -I${top_builddir} -I${top_srcdir}/include ${kinclude_CPPFLAGS} ${CPPFLAGS} @libnetfilter_conntrack_CFLAGS@ @libnftnl_CFLAGS@
+AM_CPPFLAGS = ${regular_CPPFLAGS} -I${top_builddir}/include -I${top_builddir} -I${top_srcdir}/include -I${top_srcdir} ${kinclude_CPPFLAGS} ${CPPFLAGS} @libnetfilter_conntrack_CFLAGS@ @libnftnl_CFLAGS@
AM_DEPFLAGS = -Wp,-MMD,$(@D)/.$(@F).d,-MT,$@
AM_LDFLAGS = @noundef_LDFLAGS@
diff --git a/iptables/Makefile.am b/iptables/Makefile.am
index 569a739..f92cc4f 100644
--- a/iptables/Makefile.am
+++ b/iptables/Makefile.am
@@ -1,7 +1,7 @@
# -*- Makefile -*-
AM_CFLAGS = ${regular_CFLAGS}
-AM_CPPFLAGS = ${regular_CPPFLAGS} -I${top_builddir}/include -I${top_srcdir}/include ${kinclude_CPPFLAGS} ${libmnl_CFLAGS} ${libnftnl_CFLAGS} ${libnetfilter_conntrack_CFLAGS}
+AM_CPPFLAGS = ${regular_CPPFLAGS} -I${top_builddir}/include -I${top_srcdir}/include -I${top_srcdir} ${kinclude_CPPFLAGS} ${libmnl_CFLAGS} ${libnftnl_CFLAGS} ${libnetfilter_conntrack_CFLAGS}
AM_YFLAGS = -d
BUILT_SOURCES =