FTBFS weston 8.0

[Jan Engelhardt]

It was forgotten to add the pkg-config cflags from wayland into the 
test-runner command. This causes the weston-8 build to fail, given right 
system conditions.

[    6s] [221/358] cc -Itests/59830eb@@test-runner at sta -Itests -I../tests -I. -I../ -Iinclude -I../include -fdiagnostics-color=always -pipe -D_FILE_OFFSET_BITS=64 -std=gnu99 -Wno-unused-parameter -Wno-shift-negative-value -Wno-missing-field-initializers -Wno-pedantic -fvisibility=hidden -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector-strong -funwind-tables -fasynchronous-unwind-tables -fstack-clash-protection -Werror=return-type -flto=auto -g -fPIC -MD -MQ 'tests/59830eb@@test-runner at sta/weston-test-runner.c.o' -MF 'tests/59830eb@@test-runner at sta/weston-test-runner.c.o.d' -o 'tests/59830eb@@test-runner at sta/weston-test-runner.c.o' -c ../tests/weston-test-runner.c
[    6s] FAILED: tests/59830eb@@test-runner at sta/weston-test-runner.c.o 
[    6s] cc -Itests/59830eb@@test-runner at sta -Itests -I../tests -I. -I../ -Iinclude -I../include -fdiagnostics-color=always -pipe -D_FILE_OFFSET_BITS=64 -std=gnu99 -Wno-unused-parameter -Wno-shift-negative-value -Wno-missing-field-initializers -Wno-pedantic -fvisibility=hidden -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector-strong -funwind-tables -fasynchronous-unwind-tables -fstack-clash-protection -Werror=return-type -flto=auto -g -fPIC -MD -MQ 'tests/59830eb@@test-runner at sta/weston-test-runner.c.o' -MF 'tests/59830eb@@test-runner at sta/weston-test-runner.c.o.d' -o 'tests/59830eb@@test-runner at sta/weston-test-runner.c.o' -c ../tests/weston-test-runner.c
[    6s] In file included from ../tests/weston-test-runner.c:37:
[    6s] ../tests/weston-test-runner.h:34:10: fatal error: wayland-util.h: No such file or directory