build: insert missing wayland-server-protocol dependency

A new build error sprung up in weston-14 compared to 13.0.0.
Fix it.

FAILED: tests/liblib_lcms_util.a.p/lcms_util.c.o
cc -Itests/liblib_lcms_util.a.p -Itests -I../tests -I. -I.. -Iinclude
-I../include -fdiagnostics-color=always -D_FILE_OFFSET_BITS=64 -Wall
-Winvalid-pch -Wextra -Wpedantic -std=gnu99 -Wmissing-prototypes
-Wno-unused-parameter -Wno-shift-negative-value
-Wno-missing-field-initializers -Wno-pedantic -Wundef
-fvisibility=hidden -O2 -Wall -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=3
-fstack-protector-strong -funwind-tables -fasynchronous-unwind-tables
-fstack-clash-protection -Werror=return-type -flto=auto -g -fPIC -MD
-MQ tests/liblib_lcms_util.a.p/lcms_util.c.o -MF
tests/liblib_lcms_util.a.p/lcms_util.c.o.d -o
tests/liblib_lcms_util.a.p/lcms_util.c.o -c ../tests/lcms_util.c
In file included from ../tests/lcms_util.c:35:
../include/libweston/matrix.h:33:10: fatal error:
wayland-server-protocol.h: No such file or directory

   33 | #include <wayland-server-protocol.h>

Signed-off-by: Jan Engelhardt <jengelh@inai.de>