pgsql: Remove argument isprimary from index_build()

Remove argument isprimary from index_build()

The flag was introduced in 3fdeb18, but f66e8bf actually forgot to
finish the cleanup as index_update_stats() has simplified its
interface.

Author: Michael Paquier
Discussion: https://postgr.es/m/20190122080852.GB3873@paquier.xyz

Branch
------
master

Details
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https://git.postgresql.org/pg/commitdiff/289198c0d93a3d591f379c4134e90275bd426426

Modified Files
--------------
src/backend/bootstrap/bootstrap.c |  2 +-
src/backend/catalog/heap.c        |  2 +-
src/backend/catalog/index.c       | 10 ++--------
src/backend/commands/indexcmds.c  |  2 +-
src/include/catalog/index.h       |  1 -
5 files changed, 5 insertions(+), 12 deletions(-)