meson: rework intel-rt option to be a feature

This allows intel-rt to be turned on in cases where we're on x86_64 and
we're building anv, but otherwise default to off, while still giving
users the power to ignore those defaults if they want to.

Because of the use of `feature.disable_if` this bumps the Meson
requirement to 1.1. I can get rid of that, but it just makes for a lot
more code than using the helper methods

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27645>

meson.build

@@ -23,7 +23,7 @@ project(
   ['c', 'cpp'],
   version : files('VERSION'),
   license : 'MIT',
-  meson_version : '>= 0.60',
+  meson_version : '>= 1.1.0',
   default_options : [
     'buildtype=debugoptimized',
     'b_ndebug=if-release',
@@ -303,8 +303,10 @@ else
   with_intel_clc = false
 endif
 
-with_intel_vk_rt = ['x86_64'].contains(host_machine.cpu_family()) and \
+with_intel_vk_rt = get_option('intel-rt') \
-  with_intel_vk and get_option('intel-rt') != 'disabled'
+  .disable_auto_if(not with_intel_vk) \
+  .disable_if(host_machine.cpu_family() != 'x86_64', error_message : 'Intel Ray Tracing is only supported on x86_64') \
+  .allowed()
 
 with_any_intel = [
   with_gallium_crocus,

meson_options.txt

@@ -651,12 +651,8 @@ option(
 
 option(
   'intel-rt',
-  type : 'combo',
+  type : 'feature',
   deprecated: {'true': 'enabled', 'false': 'disabled'},
-  value : 'disabled',
-  choices : [
-    'enabled', 'disabled',
-  ],
   description : 'Build Ray Tracing on supported hardware.'
 )