[libgpiod] bindings: cxx: fix building with clang's libc++

[Jan Kundrát <jan.kundrat@xxxxxxxxx>]

This is what I get on clang 11 with libc++:

 line.cpp:248:39: error: implicit instantiation of undefined template 'std::__1::array<gpiod_line_event, 16>'
         ::std::array<::gpiod_line_event, 16> event_buf;
                                              ^
 /nix/store/vk8ynr4hj2a8w7g1b9m8wknzj39iiv4x-libc++-11.0.1/include/c++/v1/__tuple:219:64: note: template is declared here
 template <class _Tp, size_t _Size> struct _LIBCPP_TEMPLATE_VIS array;

Signed-off-by: Jan Kundrát <jan.kundrat@xxxxxxxxx>
---
 bindings/cxx/line.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git bindings/cxx/line.cpp bindings/cxx/line.cpp
index bf4a3eb..9b66d1a 100644
--- bindings/cxx/line.cpp
+++ bindings/cxx/line.cpp
@@ -6,6 +6,7 @@
  */
 
 #include <gpiod.hpp>
+#include <array>
 #include <map>
 #include <system_error>
 
-- 
2.29.0