bmc-ready: new optional feature definition

This is the start of a series of commits which will enable a new feature
within phosphor-state-manager to not allow host or chassis operations if
the BMC is not in the "Ready" state.

Some systems require (and assume) all BMC services are up and running
before a chassis or host operation is started. For example IBM systems
collect VPD from i2c devices shared with the host firmware, the BMC must
complete collecting all of that VPD before the host is started. The
completion of the VPD collection is required for the BMC to reach Ready
state.

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: I0aed9323348f92dffb330089143c5f569b57a1fb
diff --git a/meson.build b/meson.build
index 08e0feb..821be9b 100644
--- a/meson.build
+++ b/meson.build
@@ -64,6 +64,9 @@
 conf.set_quoted(
     'SYSFS_TPM_MEASUREMENT_PATH', get_option('sysfs-tpm-measurement-path'))
 
+conf.set10(
+    'ONLY_ALLOW_BOOT_WHEN_BMC_READY', get_option('only-allow-boot-when-bmc-ready'))
+
 # globals shared across applications
 conf.set_quoted(
     'BASE_FILE_DIR', '/run/openbmc/')