fix 'make distcheck' by adding missing client.h to noinst_HEADERS

Change-Id: Ib2c450c902529f7327a187c612380a1f2b3ca534
diff --git a/src/Makefile.am b/src/Makefile.am
index 43a69b6..70b37de 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -12,7 +12,7 @@
 			  rspro/libosmo-asn1-rspro.la
 libosmo_rspro_la_SOURCES = rspro_util.c
 
-noinst_HEADERS = bankd.h internal.h rspro_util.h
+noinst_HEADERS = bankd.h client.h internal.h rspro_util.h
 
 bin_PROGRAMS = pcsc_test remsim-bankd remsim-client