intel: Add Meson parameter to enable Xe KMD support

The plan is to compile all the Xe files but in run time it will fail
to detect the KMD loaded and it will fall back to software
rendering(if build).

Compiling Xe files makes sure newer commits don't break Xe even if
developers don't have Xe enabled in their build folder.

Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21368>

meson.build

@@ -1428,6 +1428,10 @@ if with_any_intel and ['x86', 'x86_64'].contains(host_machine.cpu_family())
   pre_args += '-DSUPPORT_INTEL_INTEGRATED_GPUS'
 endif
 
+if get_option('intel-xe-kmd').enabled()
+  pre_args += '-DINTEL_XE_KMD_SUPPORTED'
+endif
+
 # Determine whether or not the rt library is needed for time functions
 if host_machine.system() == 'windows' or cc.has_function('clock_gettime')
   dep_clock = null_dep

meson_options.txt

@@ -630,3 +630,9 @@ option(
                 'the default driconf file is hardcoded into Mesa. ' +
                 'Requires expat.'
 )
+option (
+  'intel-xe-kmd',
+  type : 'feature',
+  value : 'disabled',
+  description: 'Enable Intel Xe KMD support.'
+)