[BUG] session: risk of crash on out of memory (1.5-dev regression)

[BUG] session: risk of crash on out of memory (1.5-dev regression)

Patch af5149 introduced an issue which can be detected only on out of
memory conditions : a LIST_DEL() may be performed on an uninitialized
struct member instead of a LIST_INIT() during the accept() phase,
causing crashes and memory corruption to occur.

This issue was detected and diagnosed by the Exceliance R&D team.

This is 1.5-specific and very recent, so no existing deployment should
be impacted.