LCMS introduces leaks in tests

A few tests now have leaks similar to this:

*** Run  color_lcms_loads/1
test-client: got global pointer 100 100
test-client: got seat 0x60700001e320 capabilities: 7
test-client: got seat 0x60700001e320 name: 'test-seat'
test-client: got keyboard repeat_info 40 400
test-client: got keyboard keymap
*** Result  color_lcms_loads/1: ok
--- Fixture 1 () ok: passed 1, skipped 0, failed 0, total 1

=================================================================
==261665==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 336 byte(s) in 6 object(s) allocated from:
    #0 0x7ff09d2ba6af in __interceptor_malloc (/lib64/libasan.so.8+0xba6af)
    #1 0x7ff09b7ad19b in _cmsMallocZeroDefaultFn (/lib64/liblcms2.so.2+0x1419b)
    #2 0x7ff09b97a09b in join_curvesets ../libweston/color-lcms/color-transform.c:372
    #3 0x7ff09b97a390 in merge_curvesets ../libweston/color-lcms/color-transform.c:419
    #4 0x7ff09b97aaec in optimize_float_pipeline ../libweston/color-lcms/color-transform.c:570
    #5 0x7ff09b97af79 in transform_factory ../libweston/color-lcms/color-transform.c:667
    #6 0x7ff09b7c8952 in AllocEmptyTransform (/lib64/liblcms2.so.2+0x2f952)
    #7 0x7ff09b7ca608 in cmsCreateMultiprofileTransformTHR.part.0 (/lib64/liblcms2.so.2+0x31608)

Indirect leak of 54048 byte(s) in 36 object(s) allocated from:
    #0 0x7ff09d2ba6af in __interceptor_malloc (/lib64/libasan.so.8+0xba6af)
    #1 0x7ff09b7ad19b in _cmsMallocZeroDefaultFn (/lib64/liblcms2.so.2+0x1419b)

Indirect leak of 24576 byte(s) in 6 object(s) allocated from: 
    #0 0x7ff09d2ba6af in __interceptor_malloc (/lib64/libasan.so.8+0xba6af)
    #1 0x7ff09b7ad1df in _cmsDupDefaultFn (/lib64/liblcms2.so.2+0x141df)

SUMMARY: AddressSanitizer: 78960 byte(s) leaked in 48 allocation(s).

(test program exited with status code 1)
==============================================================================