readme: remove redundant meson directive

Specifying -Dtests=enabled is redundant - tests are enabled by default.

Change-Id: I8d8b57c270bac7e4914c84781b61a34790a006ca
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/README.md b/README.md
index 7d25d9a..8f09ed6 100644
--- a/README.md
+++ b/README.md
@@ -7,7 +7,7 @@
 Tests can be run in the CI docker container, or with an OpenBMC x86 sdk(see
 below for x86 steps).
 ```
-meson -Doe-sdk=enabled -Dtests=enabled build
+meson -Doe-sdk=enabled build
 ninja -C build test
 ```