use-of-uninitialized-value in lxc trim whitespace in place

use-of-uninitialized-value in lxc trim whitespace in place: a task in MiMo-V2.6-RL-oss: Agentic RL Environments (MiMo RL release). MemorySanitizer: use-of-uninitialized-value in function lxc trim whitespace in place in file lxc/src/lxc/string utils.c