x86: re-enable EXECMEM_ROX support

after rework of execmem ROX caches

Signed-off-by: "Mike Rapoport (Microsoft)" <rppt@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250126074733.1384926-10-rppt@kernel.org