Fix actual clang-format version in readme

Current .clang-format requires clang-format 5.0

Signed-off-by: Andrii Chepurnyi <andrii_chepurnyi@epam.com>
diff --git a/README.md b/README.md
index 260ac9b..05f1364 100644
--- a/README.md
+++ b/README.md
@@ -11,7 +11,7 @@
 * drm_hwcomposer is Apache 2.0 Licensed and we require contributions to follow the developer's certificate of origin: http://developercertificate.org/
 * When submitting new code please follow the naming conventions documented in the generated documentation. Also please make full use of all the helpers and convenience macros provided by drm_hwcomposer. The below command can help you with formatting of your patches:
   
-      `git diff | clang-format-diff-3.5 -p 1 -style=file`
+      `git diff | clang-format-diff-5.0 -p 1 -style=file`
 * Hardware specific changes should be tested on relevant platforms before committing.
 
 If you need inspiration, please checkout our [TODO issues](https://gitlab.freedesktop.org/drm-hwcomposer/drm-hwcomposer/issues?label_name%5B%5D=TODO)