print_pc: fix multiple personalities support

* syscall.c (print_pc): Choose instruction pointer format depending
on current_wordsize, not the size of long integer type.
* tests/pc.c: New file.
* tests/pc.test: New test.
* tests/Makefile.am (check_PROGRAMS): Add pc.
(TESTS): Add pc.test.
* tests/.gitignore: Add pc.
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 731df05..e5899de 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -15,6 +15,7 @@
 	net-accept-connect \
 	netlink_inet_diag \
 	netlink_unix_diag \
+	pc \
 	scm_rights \
 	select \
 	set_ptracer_any \
@@ -60,6 +61,7 @@
 	net.test \
 	net-fd.test \
 	net-yy.test \
+	pc.test \
 	sun_path.test \
 	unix-yy.test \
 	uid.test \