Move headers under the hf directory.

This helps distinguish local headers from the more official headers.

Change-Id: I535c1b44081b9d60ba63666cd1ad514aaaf2c68d
diff --git a/.clang-format b/.clang-format
index 016cbec..c83c7f7 100644
--- a/.clang-format
+++ b/.clang-format
@@ -1,9 +1,24 @@
 BasedOnStyle: Google
+
 IndentWidth: 8
 ContinuationIndentWidth: 8
 UseTab: Always
+
 BreakBeforeBraces: Linux
 AllowShortFunctionsOnASingleLine: None
 AllowShortIfStatementsOnASingleLine: false
 AllowShortLoopsOnASingleLine: false
 IndentCaseLabels: false
+
+IncludeBlocks: Regroup
+IncludeCategories:
+  - Regex:    '^<[[:alnum:].]+>'
+    Priority: 1
+  - Regex:    '^"hf/arch/'
+    Priority: 2
+  - Regex:    '^"hf/'
+    Priority: 3
+  - Regex:    '^"vmapi/'
+    Priority: 4
+  - Regex:    '.*'
+    Priority: 5