[pgpool-committers: 4830] pgpool: Fix for 0000406: failover called with old-primary = -1

[Muhammad Usama]

Fix for 0000406: failover called with old-primary = -1

The problem is when the primary node is quarantined the current primary node id
is set to -1 (Invalid), and once after consensus is made the failover never see
the original values for and old-primary.
The fix is to restore the primary node and master node status to the older
states (before the primary node was quarantined) while processing the failover
and failback on quarantined nodes.

Branch
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V3_7_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=1648cb8c552a19b2f90de1fab120929dd5be06e4

Modified Files
--------------
src/include/pcp/libpcp_ext.h |   4 +-
src/main/pgpool_main.c       | 130 +++++++++++++++++++++++++++++++++++++------
2 files changed, 116 insertions(+), 18 deletions(-)