test: hush: Test hush if/else

As asked in commit 9c6bf1715f6a ("test/py: hush_if_test: Add tests to cover
octal/hex values"), this commit translates test_hush_if_test.py to a C test.

Signed-off-by: Francis Laniel <francis.laniel@amarulasolutions.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/test/hush/Makefile b/test/hush/Makefile
index dfa2a92..a3c9ae5 100644
--- a/test/hush/Makefile
+++ b/test/hush/Makefile
@@ -4,3 +4,4 @@
 # Francis Laniel, Amarula Solutions, francis.laniel@amarulasolutions.com
 
 obj-y += cmd_ut_hush.o
+obj-y += if.o