soft_uart: add unit tests for the receiver and transmitter

Change-Id: Icdfa0c644548964d37940c32dc9dcfcfc53c3a19
Related: OS#4396
diff --git a/tests/testsuite.at b/tests/testsuite.at
index 73c3cdc..aacdad7 100644
--- a/tests/testsuite.at
+++ b/tests/testsuite.at
@@ -513,3 +513,9 @@
 cat $abs_srcdir/osmo_io/osmo_io_test.err > experr
 AT_CHECK([$abs_top_builddir/tests/osmo_io/osmo_io_test], [0], [expout], [experr])
 AT_CLEANUP
+
+AT_SETUP([soft_uart])
+AT_KEYWORDS([soft_uart])
+cat $abs_srcdir/soft_uart/soft_uart_test.ok > expout
+AT_CHECK([$abs_top_builddir/tests/soft_uart/soft_uart_test], [0], [expout], [ignore])
+AT_CLEANUP