fix(FTBFS): meson: raise C++ standard to C++17

LLVM 16 requires this since [0] and instead of just going all over the
various directories and adding overrides it should be easier to just
raise this globally. GCC supports C++17 since GCC 8 (2018), Clang since
version 5 (2017). Debian Buster (oldstable) has GCC 8.3 and Clang 7.0,
so all major distributions should have this and there shouldn't be an
issue with bumping.

[0] <b4e9977fc1>

Closes: <https://gitlab.freedesktop.org/mesa/mesa/-/issues/7031>
Signed-off-by: Kai Wasserbäch <kai@dev.carbon-project.org>
Reviewed-by: Jesse Natalie <jenatali@microsoft.com>
Reviewed-by: David Heidelberg <david.heidelberg@collabora.com>
Reviewed-by: Ganesh Belgur Ramachandra <ganesh.belgurramachandra@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17966>

docs/install.rst

@@ -27,8 +27,8 @@ Compiler
 The following compilers are known to work, if you know of others or
 you're willing to maintain support for other compiler get in touch.
 
--  GCC 4.2.0 or later (some parts of Mesa may require later versions)
--  Clang - exact minimum requirement is currently unknown.
+-  GCC 8.0.0 or later (some parts of Mesa may require later versions)
+-  Clang 5.0 or later (some parts of Mesa may require later versions)
 -  Microsoft Visual Studio 2019 Version 16.11 or later and
    Windows SDK of at least 20348 is required, for building on Windows.
 

meson.build

@@ -27,7 +27,7 @@ project(
   ).stdout(),
   license : 'MIT',
   meson_version : '>= 0.53',
-  default_options : ['buildtype=debugoptimized', 'b_ndebug=if-release', 'c_std=c11', 'cpp_std=c++14']
+  default_options : ['buildtype=debugoptimized', 'b_ndebug=if-release', 'c_std=c11', 'cpp_std=c++17']
 )
 
 # In recent versions, meson can inject some extra arguments to get richer