Bump the trunk major version to 12

and clear the release notes.

GitOrigin-RevId: 7ab7b979d29e1e43701cf690f5cf1903740f50e3
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7065112..f20893f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -83,7 +83,7 @@
   endif()
 
   set(PACKAGE_NAME libunwind)
-  set(PACKAGE_VERSION 11.0.0git)
+  set(PACKAGE_VERSION 12.0.0git)
   set(PACKAGE_STRING "${PACKAGE_NAME} ${PACKAGE_VERSION}")
   set(PACKAGE_BUGREPORT "llvm-bugs@lists.llvm.org")
 
diff --git a/docs/conf.py b/docs/conf.py
index 70fb71f..6217ead 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -48,9 +48,9 @@
 # built documents.
 #
 # The short X.Y version.
-version = '11.0'
+version = '12.0'
 # The full version, including alpha/beta/rc tags.
-release = '11.0'
+release = '12.0'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.