libelf: Add ELF_E_INVALID_ELF error value.

Add ELF_E_INVALID_ELF which is set when the ELF file data is bad.
This is different from ELF_E_INVALID_FILE which is set when the file
could not be read.

Signed-off-by: Mark Wielaard <mark@klomp.org>
7 files changed