android: Drop gcc 7 compatibility

Now that we have dropped gcc 7 support, remove the compatibility with
gcc versions older than 8 that implemented the filesystem API in the
std::experimental namespace.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>

src/android/camera_hal_config.cpp

@@ -6,14 +6,7 @@
  */
 #include "camera_hal_config.h"
 
-#if defined(_GLIBCXX_RELEASE) && _GLIBCXX_RELEASE < 8
-#include <experimental/filesystem>
-namespace std {
-namespace filesystem = std::experimental::filesystem;
-}
-#else
 #include <filesystem>
-#endif
 #include <stdlib.h>
 #include <string>