[PATCH] tools/lib/api/fs/fs.c: Fix misuse of strncpy()

gcc 8 reports: In function 'fs__env_override', inlined from 'fs__get_mountpoint' at fs/fs.c:228:6: fs/fs.c:222:2: error: 'strncpy' specified bound 4096 equals destination size [-Werror=stringop-truncation] strncpy(fs->path, override_path, sizeof(fs->path));

[PATCH] tools/lib/api/fs/fs.c: Fix misuse of strncpy()

gcc 8 reports: In function 'fs__env_override', inlined from 'fs__get_mountpoint' at fs/fs.c:228:6: fs/fs.c:222:2: error: 'strncpy' specified bound 4096 equals destination size [-Werror=stringop-truncation] strncpy(fs->path, override_path, sizeof(fs->path));