pgsql: Remove MyAuxProcType, use MyBackendType instead

Remove MyAuxProcType, use MyBackendType instead

MyAuxProcType was redundant with MyBackendType.

Reviewed-by: Reid Thompson, Andres Freund
Discussion: https://www.postgresql.org/message-id/f3ecd4cb-85ee-4e54-8278-5fabfb3a4ed0@iki.fi

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/067701f57758f9baed5bd9d868539738d77bfa92

Modified Files
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src/backend/postmaster/auxprocess.c | 58 ++++++-----------------------
src/backend/postmaster/postmaster.c | 56 ++++++++++++++--------------
src/include/miscadmin.h             | 73 ++++++++++++++++++-------------------
src/include/postmaster/auxprocess.h |  2 +-
src/tools/pgindent/typedefs.list    |  1 -
5 files changed, 75 insertions(+), 115 deletions(-)