Add --display-orientation

Deprecate the option --rotation and introduce a new option
--display-orientation with the 8 possible orientations (0, 90, 180, 270,
flip0, flip90, flip180 and flip270).

New shortcuts MOD+Shift+(arrow) dynamically change the display
(horizontal or vertical) flip.

Fixes #1380 <https://github.com/Genymobile/scrcpy/issues/1380>
Fixes #3819 <https://github.com/Genymobile/scrcpy/issues/3819>
PR #4441 <https://github.com/Genymobile/scrcpy/pull/4441>

app/meson.build

@@ -289,6 +289,10 @@ if get_option('buildtype') == 'debug'
             'tests/test_device_msg_deserialize.c',
             'src/device_msg.c',
         ]],
+        ['test_orientation', [
+            'tests/test_orientation.c',
+            'src/options.c',
+        ]],
         ['test_strbuf', [
             'tests/test_strbuf.c',
             'src/util/strbuf.c',