drm_hwcomposer: CI: Set clang-format-diff context line number to 0

To avoid false CI failures, triggered when context lines are not
properly formatted.

Change-Id: Ia10049a63b57616bd59763e22f246266869aabd6
Signed-off-by: Roman Stratiienko <r.stratiienko@gmail.com>
diff --git a/.ci/.gitlab-ci-checkcommit.sh b/.ci/.gitlab-ci-checkcommit.sh
index 3f597c3..1ca2876 100755
--- a/.ci/.gitlab-ci-checkcommit.sh
+++ b/.ci/.gitlab-ci-checkcommit.sh
@@ -61,7 +61,7 @@
 		exit 1
 	fi
 
-	git show "$h" -- | clang-format-diff-19 -p 1 -style=file > /tmp/format-fixup.patch
+	git show -U0 "$h" -- | clang-format-diff-19 -p 1 -style=file > /tmp/format-fixup.patch
 	if [ -s  /tmp/format-fixup.patch ]; then
 		cat /tmp/format-fixup.patch >&2
 		exit 1