[json-glib] docs: Update list of requirements

[Emmanuele Bassi <ebassi src gnome org>]

commit b3592048454b51325f2d6a8006e4e15cd3c93f7e
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Mon Jul 10 16:26:09 2017 +0100

    docs: Update list of requirements
    
    Both gtk-doc and gobject-introspection are optional.

 README.md |    8 ++------
 1 files changed, 2 insertions(+), 6 deletions(-)
---
diff --git a/README.md b/README.md
index 2149450..f002fda 100644
--- a/README.md
+++ b/README.md
@@ -32,13 +32,9 @@ In order to build JSON-GLib you will need:
  * [ninja](http://ninja-build.org)
  * [meson](http://mesonbuild.com)
  * pkg-config
- * gtk-doc ≥ 1.13
+ * gtk-doc ≥ 1.13 (optional)
  * GLib, GIO ≥ 2.38
-
-Optionally, JSON-GLib depends on:
-
- * GObject-Introspection ≥ 1.38
- * LCov ≥ 1.6
+ * GObject-Introspection ≥ 1.38 (optional)
 
 INSTALLATION
 --------------------------------------------------------------------------------