[libchamplain] Remove building instructions using autotools from README.md

[Jiří Techet <jiritechet src gnome org>]

commit cd9e582bed3fbaf4981e789a1e4224ebefc5e964
Author: Jiří Techet <techet gmail com>
Date:   Sat Feb 9 19:41:00 2019 +0100

    Remove building instructions using autotools from README.md

 README.md | 5 -----
 1 file changed, 5 deletions(-)
---
diff --git a/README.md b/README.md
index e5fc94c..4a7d6e7 100644
--- a/README.md
+++ b/README.md
@@ -20,11 +20,6 @@ To build libchamplain from sources using meson, run:
 meson _builddir; cd _builddir; ninja; sudo ninja install
 ```
 
-Alternatively, when using autotools, run:
-```
-./autogen.sh; make; sudo make install
-```
-
 The **repository and bug report** page is at:
 * https://gitlab.gnome.org/GNOME/libchamplain