Print flags as documented in MS docs.
https://docs.microsoft.com/en-us/windows/win32/debug/pe-format#load-configuration-layout
https://docs.microsoft.com/en-us/windows/win32/secbp/pe-metadata
EH_CONTINUATION_TABLE_PRESENT is not mentioned in the docs but is
instead taken from Windows SDK headers.
Please replace the existing coff_guard_flags enum with the new enum that you just added. It only has 7 hits across the codebase, but some are in LLD. That can also be a follow up CL, if you prefer, but I don't want to carry both duplicate enums long term.