pgsql: Fix SIGUSR1 handling by unconnected bgworkers

Fix SIGUSR1 handling by unconnected bgworkers

Latch activity was not being detected by non-database-connected workers; the
SIGUSR1 signal handler which is normally in charge of that was set to SIG_IGN.
Create a simple handler to call latch_sigusr1_handler instead.

Robert Haas (bug report and suggested fix)

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/f62ab623adc63023c6aee22e2a6fe190439ca0c3

Modified Files
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src/backend/postmaster/postmaster.c |   18 +++++++++++++++++-
1 files changed, 17 insertions(+), 1 deletions(-)