meson: Create and use a dependency for libcamera and its headers

Instead of manually adding the libcamera library and include path to
every target that requires it, declare a dependency that groups the
headers as source, the library and the include path, and use it through
the project. This simplifies handling of the dependency.

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

test/v4l2_device/meson.build

@@ -11,6 +11,7 @@ v4l2_device_tests = [
 
 foreach t : v4l2_device_tests
     exe = executable(t[0], [t[1], 'v4l2_device_test.cpp'],
+                     dependencies : libcamera_dep,
                      link_with : test_libraries,
                      include_directories : test_includes_internal)
     test(t[0], exe, suite : 'v4l2_device', is_parallel : false)