build: shells do not need matrix.c

Do not build matrix.c into the shell plugins. The matrix functions are exported
by libweston.so and the shell plugins links to it.

Found by inspection.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>

desktop-shell/meson.build

@@ -5,7 +5,6 @@ if get_option('shell-desktop')
 		'shell.c',
 		'exposay.c',
 		'input-panel.c',
-		'../shared/matrix.c',
 		weston_desktop_shell_server_protocol_h,
 		weston_desktop_shell_protocol_c,
 		input_method_unstable_v1_server_protocol_h,

fullscreen-shell/meson.build

@@ -1,7 +1,6 @@
 if get_option('shell-fullscreen')
 	srcs_shell_fullscreen = [
 		'fullscreen-shell.c',
-		'../shared/matrix.c',
 		fullscreen_shell_unstable_v1_server_protocol_h,
 		fullscreen_shell_unstable_v1_protocol_c,
 	]