src/Makefile.am: correct compile failure for launcher-util.c
src/Makefile.am: correct compile failure for launcher-util.c

The following error message is generated during compile
In file included from launcher-util.c:43:0:
compositor.h:35:28: fatal error: wayland-server.h: No such file or directory
 #include <wayland-server.h>

Signed-off-by: Xiong Zhang <887154684953c1d7bc9f653d05b20c8de98c15bc@intel.com>

xorgy/weston,Fantu/compositor-spice,kwm81/weston,Gnurou/weston,krezovic/weston,Gnurou/weston,jonnylamb/weston,giucam/weston,Tarnyko/weston-xdg_surface_present,Fantu/compositor-spice,sir-murray/weston,udoprog/weston,eyolfson/weston,xorgy/weston,jonnylamb/weston,sir-murray/weston,giucam/weston,mchalupa/weston,mchalupa/weston,krezovic/weston,Tarnyko/weston-xdg_surface_present,udoprog/weston,kwm81/weston,Fantu/compositor-spice,eyolfson/weston