graphics/frogr: fix typo in Meson option name

meson.build:1:0: ERROR: Unknown options: "warnlevel"

https://gitlab.gnome.org/GNOME/frogr/-/commit/623d7e397baf

PR:		259080
Reported by:	antoine (via exp-run)
Regressed by:	https://github.com/mesonbuild/meson/commit/dbf2ace6ca1c

frogr

graphics/frogr/files/patch-meson.build

@@ -1,10 +1,12 @@
 --- meson.build.orig	2020-01-10 22:37:55 UTC
 +++ meson.build
-@@ -3,7 +3,7 @@ project('frogr', 'c',
+@@ -2,8 +2,8 @@ project('frogr', 'c',
+         version: '1.6',
          license: 'GPL3',
          default_options: [
-             'warnlevel=2',
+-            'warnlevel=2',
 -            'werror=true'
++            'warning_level=2',
 +            'werror=false'
          ])