meson: Remove -Wno-unused-parameter

We build libcamera with -Wno-unused-parameter and this doesn't cause
much issue internally. However, it prevents catching unused parameters
in inline functions defined in public headers. This can lead to
compilation warnings for applications compiled without
-Wno-unused-parameter.

To catch those issues, remove -Wno-unused-parameter and fix all the
related warnings with [[maybe_unused]].

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>

src/ipa/raspberrypi/controller/rpi/agc.cpp

@@ -221,7 +221,8 @@ void Agc::SetConstraintMode(std::string const &constraint_mode_name)
 	constraint_mode_name_ = constraint_mode_name;
 }
 
-void Agc::SwitchMode(CameraMode const &camera_mode, Metadata *metadata)
+void Agc::SwitchMode([[maybe_unused]] CameraMode const &camera_mode,
+		     Metadata *metadata)
 {
 	// On a mode switch, it's possible the exposure profile could change,
 	// so we run through the dividing up of exposure/gain again and

src/ipa/raspberrypi/raspberrypi.cpp

@@ -191,7 +191,7 @@ void IPARPi::setMode(const CameraSensorInfo &sensorInfo)
 }
 
 void IPARPi::configure(const CameraSensorInfo &sensorInfo,
-		       const std::map<unsigned int, IPAStream> &streamConfig,
+		       [[maybe_unused]] const std::map<unsigned int, IPAStream> &streamConfig,
 		       const std::map<unsigned int, const ControlInfoMap &> &entityControls,
 		       const IPAOperationData &ipaConfig,
 		       IPAOperationData *result)

src/ipa/rkisp1/rkisp1.cpp

@@ -32,7 +32,10 @@ LOG_DEFINE_CATEGORY(IPARkISP1)
 class IPARkISP1 : public IPAInterface
 {
 public:
-	int init(const IPASettings &settings) override { return 0; }
+	int init([[maybe_unused]] const IPASettings &settings) override
+	{
+		return 0;
+	}
 	int start() override { return 0; }
 	void stop() override {}
 
@@ -75,11 +78,11 @@ private:
  * assemble one. Make sure the reported sensor information are relevant
  * before accessing them.
  */
-void IPARkISP1::configure(const CameraSensorInfo &info,
-			  const std::map<unsigned int, IPAStream> &streamConfig,
+void IPARkISP1::configure([[maybe_unused]] const CameraSensorInfo &info,
+			  [[maybe_unused]] const std::map<unsigned int, IPAStream> &streamConfig,
 			  const std::map<unsigned int, const ControlInfoMap &> &entityControls,
-			  const IPAOperationData &ipaConfig,
-			  IPAOperationData *result)
+			  [[maybe_unused]] const IPAOperationData &ipaConfig,
+			  [[maybe_unused]] IPAOperationData *result)
 {
 	if (entityControls.empty())
 		return;

src/ipa/vimc/vimc.cpp

@@ -37,14 +37,14 @@ public:
 	int start() override;
 	void stop() override;
 
-	void configure(const CameraSensorInfo &sensorInfo,
-		       const std::map<unsigned int, IPAStream> &streamConfig,
-		       const std::map<unsigned int, const ControlInfoMap &> &entityControls,
-		       const IPAOperationData &ipaConfig,
-		       IPAOperationData *result) override {}
-	void mapBuffers(const std::vector<IPABuffer> &buffers) override {}
-	void unmapBuffers(const std::vector<unsigned int> &ids) override {}
-	void processEvent(const IPAOperationData &event) override {}
+	void configure([[maybe_unused]] const CameraSensorInfo &sensorInfo,
+		       [[maybe_unused]] const std::map<unsigned int, IPAStream> &streamConfig,
+		       [[maybe_unused]] const std::map<unsigned int, const ControlInfoMap &> &entityControls,
+		       [[maybe_unused]] const IPAOperationData &ipaConfig,
+		       [[maybe_unused]] IPAOperationData *result) override {}
+	void mapBuffers([[maybe_unused]] const std::vector<IPABuffer> &buffers) override {}
+	void unmapBuffers([[maybe_unused]] const std::vector<unsigned int> &ids) override {}
+	void processEvent([[maybe_unused]] const IPAOperationData &event) override {}
 
 private:
 	void initTrace();