meson: add docs option to enable/disable generating documentation

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>

libvirt.spec.in

@@ -1184,6 +1184,7 @@ export SOURCE_DATE_EPOCH=$(stat --printf='%Y' %{_specdir}/%{name}.spec)
            %{?enable_werror} \
            -Dexpensive_tests=enabled \
            -Dinit_script=systemd \
+           -Ddocs=enabled \
            %{?arg_login_shell}
 
 %meson_build

meson.build

@@ -2203,7 +2203,10 @@ subdir('examples')
 
 subdir('po')
 
-subdir('docs')
+gen_docs = not get_option('docs').disabled()
+if gen_docs
+  subdir('docs')
+endif
 
 subdir('build-aux')
 
@@ -2428,6 +2431,7 @@ endif
 misc_summary = {
   'Use -Werror': cc_flags.contains('-Werror'),
   'Warning Flags': supported_cc_flags,
+  'docs': gen_docs,
   'DTrace': conf.has('WITH_DTRACE_PROBES'),
   'firewalld': conf.has('WITH_FIREWALLD'),
   'firewalld-zone': conf.has('WITH_FIREWALLD_ZONE'),

meson_options.txt

@@ -7,6 +7,7 @@ option('expensive_tests', type: 'feature', value: 'auto', description: 'set the
 option('test_coverage', type: 'boolean', value: false, description: 'turn on code coverage instrumentation')
 option('git_werror', type: 'feature', value: 'auto', description: 'use -Werror if building from GIT')
 option('rpath', type: 'feature', value: 'auto', description: 'whether to include rpath information in installed binaries and libraries')
+option('docs', type: 'feature', value: 'auto', description: 'whether to generate documentation')
 
 
 # build dependencies options