[clang-tools-extra] Cleanup documentation routine

The following issues are resolved:

* Doxygen didn't generate documentation for a bunch of existing tools
due to the absence of their directories in the doxygen configuration
file. This patch adds all relevant directories to the appropriate list.

* clang-tools-extra/docs/Doxyfile seems to be unused and irrelevant,
doxygen.cfg.in is passed to the CMake's Doxygen invocation, hence
Doxyfile is removed.

The validity of proposed changes was manually checked by building
doxygen-clang-tools and making sure that clangd and other tools are
present in Doxygen-generated docs of clang-tools-extra.

Reviewers: ioeric

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D47537

llvm-svn: 336257
diff --git a/clang-tools-extra/docs/doxygen.cfg.in b/clang-tools-extra/docs/doxygen.cfg.in
index 6dbf6db..8809588 100644
--- a/clang-tools-extra/docs/doxygen.cfg.in
+++ b/clang-tools-extra/docs/doxygen.cfg.in
@@ -743,15 +743,20 @@
 # spaces.
 # Note: If this tag is empty the current directory is searched.
 
-INPUT                  = \
-                         @abs_srcdir@/../clang-tidy \
-                         @abs_srcdir@/../clang-apply-replacements \
-                         @abs_srcdir@/../clang-query \
-                         @abs_srcdir@/../clang-rename \
-                         @abs_srcdir@/../modularize \
-                         @abs_srcdir@/../pp-trace \
-                         @abs_srcdir@/../tool-template \
-                         @abs_srcdir@/doxygen-mainpage.dox
+INPUT                  =  \
+                          @abs_srcdir@/../change-namespace \
+                          @abs_srcdir@/../clang-apply-replacements \
+                          @abs_srcdir@/../clang-doc \
+                          @abs_srcdir@/../clang-move \
+                          @abs_srcdir@/../clang-query \
+                          @abs_srcdir@/../clang-reorder-fields \
+                          @abs_srcdir@/../clang-tidy \
+                          @abs_srcdir@/../clangd \
+                          @abs_srcdir@/../include-fixer \
+                          @abs_srcdir@/../modularize \
+                          @abs_srcdir@/../pp-trace \
+                          @abs_srcdir@/../tool-template \
+                          @abs_srcdir@/doxygen-mainpage.dox
 
 # This tag can be used to specify the character encoding of the source files
 # that doxygen parses. Internally doxygen uses the UTF-8 encoding. Doxygen uses