UPSTREAM: build: version bump to flag existence of new API (DTMF)

Burst and continuous DTMF support was added.

Change-Id: I925e19ae07ec556a4586601aeae77787febc7d37
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/libqmi/+/3777353
Commit-Queue: Pavan Holla <pholla@google.com>
Reviewed-by: Eric Caruso <ejcaruso@chromium.org>
Tested-by: Pavan Holla <pholla@google.com>
diff --git a/meson.build b/meson.build
index ccccc24..a965d2b 100644
--- a/meson.build
+++ b/meson.build
@@ -3,7 +3,7 @@
 
 project(
   'libqmi', 'c',
-  version: '1.31.8',
+  version: '1.31.9',
   license: 'GPL2',
   default_options: [
     'buildtype=debugoptimized',