dtoc: Rename the main module

Python does not like the module name being the same as the module
directory. To allow dtoc modules to be used from other tools, rename
it.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/dtoc/dtoc b/tools/dtoc/dtoc
index 896ca44..11a5d8e 120000
--- a/tools/dtoc/dtoc
+++ b/tools/dtoc/dtoc
@@ -1 +1 @@
-dtoc.py
\ No newline at end of file
+main.py
\ No newline at end of file
diff --git a/tools/dtoc/dtoc.py b/tools/dtoc/main.py
similarity index 98%
rename from tools/dtoc/dtoc.py
rename to tools/dtoc/main.py
index 8e05b43..b1eee21 100755
--- a/tools/dtoc/dtoc.py
+++ b/tools/dtoc/main.py
@@ -77,7 +77,7 @@
 def RunTestCoverage():
     """Run the tests and check that we get 100% coverage"""
     sys.argv = [sys.argv[0]]
-    test_util.RunTestCoverage('tools/dtoc/dtoc.py', '/dtoc.py',
+    test_util.RunTestCoverage('tools/dtoc/dtoc', '/main.py',
             ['tools/patman/*.py', '*/fdt*', '*test*'], options.build_dir)