Add ResolveRootBus and IsRootBusInhibited to HwmonSysfs, implemented by
I2cSysfs. IXcHwmonBasedSensor uses them to report a bus inhibit reason, so
HwmonBasedSensor::RefreshOnceAsync skips sysfs I/O and reports STATUS_STALE
while mfgd holds an inhibit file for the root I2C bus.

Google-Bug-Id:566321613
PiperOrigin-RevId: 994150372
Change-Id: If8b73a706406e834ded1c5306dfb434d07542670

gbmcweb

diff --git a/gbmcweb b/gbmcweb
index a349f99..a1cc823 160000
--- a/gbmcweb
+++ b/gbmcweb
@@ -1 +1 @@
-Subproject commit a349f99c81d72a8f510a2cec49db2b238e7cb472
+Subproject commit a1cc82366d9eb8dd6fcda15d4737c0cab3dc8342