drm_hwcomposer: CI: Bump-up clang toolchain to v15

Address new clang-tidy findings, in most cases 'misc-const-correctness'
check was addressed by adding 'const' modifier, or in some cases changed
to 'auto' (where it's better for formatting).

Signed-off-by: Roman Stratiienko <r.stratiienko@gmail.com>
diff --git a/compositor/LayerData.h b/compositor/LayerData.h
index d04514d..92d4da0 100644
--- a/compositor/LayerData.h
+++ b/compositor/LayerData.h
@@ -49,14 +49,14 @@
   hwc_rect_t display_frame{};
 
   bool RequireScalingOrPhasing() const {
-    float src_width = source_crop.right - source_crop.left;
-    float src_height = source_crop.bottom - source_crop.top;
+    const float src_width = source_crop.right - source_crop.left;
+    const float src_height = source_crop.bottom - source_crop.top;
 
     auto dest_width = float(display_frame.right - display_frame.left);
     auto dest_height = float(display_frame.bottom - display_frame.top);
 
-    bool scaling = src_width != dest_width || src_height != dest_height;
-    bool phasing = (source_crop.left - std::floor(source_crop.left) != 0) ||
+    auto scaling = src_width != dest_width || src_height != dest_height;
+    auto phasing = (source_crop.left - std::floor(source_crop.left) != 0) ||
                    (source_crop.top - std::floor(source_crop.top) != 0);
     return scaling || phasing;
   }