meson_options.txt: Support for reading options from meson.options

Support has been added for reading options from meson.options instead
of meson_options.txt[1]. These are equivalent, but not using the .txt
extension for a build file has a few advantages, chief among them
many tools and text editors expect a file with the .txt extension to
be plain text files, not build scripts.

[1] https://mesonbuild.com/Release-notes-for-1-1-0.html#support-for-reading-options-from-mesonoptions

Signed-off-by: George Liu <liuxiwei@inspur.com>
Change-Id: I5b15799664fc2594b6095ed82fed92f87769a3b8
diff --git a/README.md b/README.md
index 4cdad32..314679d 100644
--- a/README.md
+++ b/README.md
@@ -31,8 +31,8 @@
   rm -rf build
 ```
 
-You can specify [meson options](meson_options.txt) to customize the build
-process. For example, you can specify:
+You can specify [meson options](meson.options) to customize the build process.
+For example, you can specify:
 
 - Which applications to build and install.
 - Application-specific configuration data, such as power sequencer type.
diff --git a/meson_options.txt b/meson.options
similarity index 100%
rename from meson_options.txt
rename to meson.options