libcamera: Adapt Vector class to new location

Change the namespace of the Vector class from libipa to libcamera and
add it to the build.

Signed-off-by: Stefan Klug <stefan.klug@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

test/meson.build

@@ -73,6 +73,7 @@ internal_tests = [
     {'name': 'timer-thread', 'sources': ['timer-thread.cpp']},
     {'name': 'unique-fd', 'sources': ['unique-fd.cpp']},
     {'name': 'utils', 'sources': ['utils.cpp']},
+    {'name': 'vector', 'sources': ['vector.cpp']},
     {'name': 'yaml-parser', 'sources': ['yaml-parser.cpp']},
 ]