Replace pragma once with include guards

Signed-off-by: Martin Stump <martin.stump@mercedes-benz.com>

include/MantleAPI/Common/i_logger.h

@@ -8,7 +8,8 @@
  * SPDX-License-Identifier: EPL-2.0
  *******************************************************************************/
 
-#pragma once
+#ifndef MANTLEAPI_COMMON_I_LOGGER_H
+#define MANTLEAPI_COMMON_I_LOGGER_H
 
 #include <string_view>
 
@@ -64,3 +65,5 @@ public:
 };
 
 }  // namespace mantle_api
+
+#endif  // MANTLEAPI_COMMON_I_LOGGER_H

include/MantleAPI/Common/log_utils.h

@@ -8,11 +8,13 @@
  * SPDX-License-Identifier: EPL-2.0
  *******************************************************************************/
 
-#pragma once
+#ifndef MANTLEAPI_COMMON_LOG_UTILS_H
+#define MANTLEAPI_COMMON_LOG_UTILS_H
 
 #include <MantleAPI/Common/i_logger.h>
 
 #include <array>
+#include <ostream>
 #include <string_view>
 
 namespace mantle_api
@@ -23,13 +25,13 @@ namespace log_utils
 
 static inline constexpr auto kLogLevelNames = std::array<std::string_view, 6>{"Trace", "Debug", "Info", "Warning", "Error", "Critical"};
 
-[[nodiscard]] inline constexpr auto ToStringView(LogLevel level) noexcept -> std::string_view
+[[nodiscard]] constexpr auto ToStringView(LogLevel level) noexcept -> std::string_view
 {
   return (level >= LogLevel::kTrace && level <= LogLevel::kCritical) ? kLogLevelNames.at(static_cast<size_t>(level)) : "Log level out of range";
 }
 
 template <LogLevel Level>
-[[nodiscard]] inline constexpr auto ToStringView() noexcept -> std::string_view
+[[nodiscard]] constexpr auto ToStringView() noexcept -> std::string_view
 {
   static_assert(Level >= LogLevel::kTrace && Level <= LogLevel::kCritical, "Log level out of range");
   return ToStringView(Level);
@@ -44,3 +46,5 @@ inline auto operator<<(std::ostream& os, mantle_api::LogLevel level) noexcept ->
 }
 
 }  // namespace mantle_api
+
+#endif  // MANTLEAPI_COMMON_LOG_UTILS_H

test/MantleAPI/Common/mock_logger.h

@@ -8,12 +8,13 @@
  * SPDX-License-Identifier: EPL-2.0
  *******************************************************************************/
 
-#pragma once
+#ifndef MANTLEAPI_COMMON_MOCK_LOGGER_H
+#define MANTLEAPI_COMMON_MOCK_LOGGER_H
 
 #include <gmock/gmock.h>
 
 #include <iomanip>
-#include <iostream>
+#include <ostream>
 
 #include "MantleAPI/Common/i_logger.h"
 #include "MantleAPI/Common/log_utils.h"
@@ -41,3 +42,5 @@ public:
 };
 
 }  // namespace mantle_api
+
+#endif  // MANTLEAPI_COMMON_MOCK_LOGGER_H