Add option to disable tests.

Upstream-Status: Submitted (https://github.com/anholt/libepoxy/pull/158)
Signed-off-by: Ross Burton <ross.burton@intel.com>

diff --git a/meson.build b/meson.build
index b2ebaef..9632c7a 100644
--- a/meson.build
+++ b/meson.build
@@ -242,7 +242,10 @@ libepoxy_inc = [
 
 subdir('include/epoxy')
 subdir('src')
-subdir('test')
+
+if get_option('tests')
+  subdir('test')
+endif
 
 if get_option('docs')
   doxygen = find_program('doxygen', required: false)
diff --git a/meson_options.txt b/meson_options.txt
index b5d7c98..dc30e68 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -15,3 +15,7 @@ option('x11',
        type: 'boolean',
        value: true,
        description: 'Enable X11 support (GLX or EGL-X11)')
+option('tests',
+       type: 'boolean',
+       value: true,
+       description: 'Build the test suite')