add missing header

When compiling with gcc15, compiliation fails with the following error:

| In file included from ../sources/libcamera-apps-1.9.0/post_processing_stages/segmentation_tf_stage.cpp:8:
| ../sources/libcamera-apps-1.9.0/post_processing_stages/segmentation.hpp:15:82: error: 'uint8_t' was not declared in this scope
|    15 |         Segmentation(int w, int h, std::vector<std::string> l, const std::vector<uint8_t> &s)

To avoid it, add the cstdint header to the offending file.

Signed-off-by: Gyorgy Sarvari <[email protected]>

Author: OldManYellsAtCloud

post_processing_stages/segmentation.hpp

@@ -7,6 +7,7 @@
 
 #pragma once
 
+#include <cstdint>
 #include <string>
 #include <vector>