[mutter] meson: Enable -Wall by default

[Marge Bot <marge-bot src gnome org>]

commit 1ae8f000c1d117fd7aec27c632a82341b44b7dff
Author: Dor Askayo <dor askayo gmail com>
Date:   Sat Feb 19 17:29:19 2022 +0200

    meson: Enable -Wall by default
    
    Some redundant flags which implied by other flags were removed.
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2301>

 meson.build | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)
---
diff --git a/meson.build b/meson.build
index 5041755492..b6522f93d3 100644
--- a/meson.build
+++ b/meson.build
@@ -378,12 +378,10 @@ buildtype = get_option('buildtype')
 if buildtype != 'plain'
   all_warnings = [
     '-fno-strict-aliasing',
+    '-Wall',
     '-Wpointer-arith',
     '-Wmissing-declarations',
-    '-Wimplicit-function-declaration',
     '-Wformat=2',
-    '-Wformat-nonliteral',
-    '-Wformat-security',
     '-Wstrict-prototypes',
     '-Wmissing-prototypes',
     '-Wnested-externs',