[SYCL][clang] Fix more free-function kernel integration header cases#20877

steffenlarsen wants to merge 8 commits intointel:syclintel/llvm:syclfrom

steffenlarsen:steffen/fix_more_ff_int_header_casessteffenlarsen/llvm:steffen/fix_more_ff_int_header_casesCopy head branch name to clipboard