buildman: Add gcc 4.9.0 with Microblaze toolchain

Also read gcc 4.9.0 at kernel.org which also have Microblaze toolchain.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>

Fixed unit test failure by updating the test:
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/buildman/toolchain.py b/tools/buildman/toolchain.py
index 051da11..e33e105 100644
--- a/tools/buildman/toolchain.py
+++ b/tools/buildman/toolchain.py
@@ -339,7 +339,7 @@
         """
         arch = command.OutputOneLine('uname', '-m')
         base = 'https://www.kernel.org/pub/tools/crosstool/files/bin'
-        versions = ['4.6.3', '4.6.2', '4.5.1', '4.2.4']
+        versions = ['4.9.0', '4.6.3', '4.6.2', '4.5.1', '4.2.4']
         links = []
         for version in versions:
             url = '%s/%s/%s/' % (base, arch, version)