added target to build for Android

We use virtualsmartcard's libpcsclite to connect to a smartcard. The
PC/SC service with vicc-interface is implemented elsewhere (currently
un-free).

npa/Makefile.am

@@ -1,5 +1,5 @@
 ACLOCAL_AMFLAGS = -I m4
-SUBDIRS = src m4 doc win32 certs
+SUBDIRS = src m4 doc cross certs
 
 EXTRA_DIST = libnpa.pc.in apdus test_vicc_with_npa-tool.sh
 
@@ -22,7 +22,10 @@ libnpa.pc: libnpa.pc.in
 	$(do_subst) < $(srcdir)/libnpa.pc.in > libnpa.pc
 
 win:
-	make -C win32 $@
+	make -C cross $@
+
+android:
+	make -C cross $@
 
 clean-local:
 	rm -f libnpa.pc