pgsql: Remove configure flag --disable-shared, as it is no longer used

Remove configure flag --disable-shared, as it is no longer used by any
port. The last use was QNX, per Peter Eisentraut.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/381a9ed66d8a601eb972be172e7251ca7f0e9d78

Modified Files
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configure | 33 ------------------------
configure.in | 7 -----
src/Makefile.global.in | 8 ------
src/Makefile.shlib | 18 -------------
src/backend/snowball/Makefile | 4 ---
src/backend/utils/mb/conversion_procs/Makefile | 4 ---
6 files changed, 0 insertions(+), 74 deletions(-)