Pin thermanager repo to o-mr1 branch

Upstream now assumes libxml2 can be linked without libicuuc,
which is only the case for newer base versions of Android.

Change-Id: I52bfeb0d6e0784e40266f4087f8b049d542dceca

default.xml

@@ -593,7 +593,7 @@
   <project name="repo_update" path="vendor/oss/repo_update" remote="sony" revision="android-8.1.0_r3">
     <linkfile dest="repo_update.sh" src="repo_update.sh"/>
   </project>
-  <project name="thermanager" path="vendor/oss/thermanager" remote="sony" revision="master"/>
+  <project name="thermanager" path="vendor/oss/thermanager" remote="sony" revision="o-mr1"/>
   <project name="timekeep" path="vendor/oss/timekeep" remote="sony" revision="master"/>
   <project name="toolchain/binutils"/>
   <project name="transpower" path="vendor/oss/transpower" remote="sony" revision="android-8.1.0_r35"/>