LoongArch ioctl bindings omit FIEMAP constants

[wojiushixiaobai]

linux_raw_sys::ioctl on loongarch64 does not expose the FIEMAP constants
added in #97, such as FIEMAP_EXTENT_LAST, FIEMAP_EXTENT_SHARED, and
FIEMAP_EXTENT_DATA_INLINE.

gen/ioctl/list.c requests these constants, and generated bindings for other
architectures contain them. However, LoongArch uses the static fallback:

cat loongarch-ioctls.txt >> "$out"

The static gen/ioctl/loongarch-ioctls.txt contains FS_IOC_FIEMAP, but no
FIEMAP_* definitions at all. Consequently,
src/loongarch64/ioctl.rs contains FS_IOC_FIEMAP but no
FIEMAP_EXTENT_* constants.

This appears to have started when #97 added the FIEMAP requests: the LoongArch
static snapshot was not regenerated/updated. Commit #174 retained the static
fallback while updating the general generator, but did not modify this file.