compression: test: Move test into lib

This test doesn't belong at the top level. Move it into the lib/
directory, since that is where compression is implemented.

Signed-off-by: Simon Glass <sjg@chromium.org>
Tested-by: Tom Rini <trini@konsulko.com> # rpi_3, rpi_4, rpi_arm64, am64x_evm_a53, am64-sk
diff --git a/test/lib/Makefile b/test/lib/Makefile
index a54387a..ce22780 100644
--- a/test/lib/Makefile
+++ b/test/lib/Makefile
@@ -2,6 +2,9 @@
 #
 # (C) Copyright 2018
 # Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc
+
+obj-$(CONFIG_$(XPL_)UT_COMPRESSION) += compression.o
+
 ifeq ($(CONFIG_XPL_BUILD),)
 obj-y += cmd_ut_lib.o
 obj-y += abuf.o