xkbcomp/scanner: avoid unneeded strdup of IDENT tokens The allocation is immediately discarded, either turned into a keysym or an atom. So use an sval slice into the input string instead strdup'ing. memusage ./release/bench-compile-keymap --iter=1000 --layout us,de --variant ,neo Before: Memory usage summary: heap total: 534063576, heap peak: 581022, stack peak: 18848 total calls total memory failed calls malloc| 11240525 291897104 0 realloc| 1447657 192307328 0 (nomove:37629, dec:0, free:0) calloc| 430573 49859144 0 free| 13993903 534063576 After: Memory usage summary: heap total: 506839909, heap peak: 581022, stack peak: 18960 total calls total memory failed calls malloc| 8016419 264673437 0 realloc| 1447657 192307328 0 (nomove:37278, dec:0, free:0) calloc| 430573 49859144 0 free| 10769797 506839909 Signed-off-by: Ran Benita <ran@unusedvar.com>