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

Since meson 1.1.0, 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: I3f82024a310fdb858377066c50711a068d2c8def
diff --git a/meson_options.txt b/meson.options
similarity index 100%
rename from meson_options.txt
rename to meson.options