RHBZ-1944096 - assertion failure during self comparison of systemd

RHBZ-1944096 - assertion failure during self comparison of systemd

When reading the abixml representing an enumerator which value is
exactly either LLONG_MIN or LLONG_MAX, build_enum_type_decl fails
because we wrongly think that an underflow or overflow happened, while
using strtoll.

This patch fixes the condition used to detect {under,over}flow
whenusing strtoll.

	* src/abg-reader.cc (build_enum_type_decl): When strtoll detects
	an underflow or overflo, it sets errno to ERANGE.  So take that
	into account.

Signed-off-by: Dodji Seketeli <dodji@redhat.com>