New release: v1.20
    btf_encoder:
    Improve ELF error reporting using elf_errmsg(elf_errno())
    Improve objcopy error handling.
    Fix handling of 'restrict' qualifier, that was being treated as a 'const'.
    Support SHN_XINDEX in st_shndx symbol indexes
    Cope with functions without a name
    Fix BTF variable generation for kernel modules
    Fix address size to match what is in the ELF file being processed.
    Use kernel module ftrace addresses when finding which functions to encode.
    libbpf:
    Allow use of packaged version.
    dwarf_loader:
    Support DW_AT_data_bit_offset
    DW_FORM_implicit_const in attr_numeric() and attr_offset()
    Support DW_TAG_GNU_call_site, standardized rename of DW_TAG_GNU_call_site.
    build:
    Fix compilation on 32-bit architectures.