pgsql: Revert "Prevent running pg_basebackup as root"

Revert "Prevent running pg_basebackup as root"

This reverts commit 7bae0ad, as this is not ideal with the tar format,
and we may want to explore more options like what is done by tar with
some equivalents of --owner and --group, but for pg_basebackup.

Per complaints from Magnus Hagander and Stephen Frost.

Discussion: https://postgr.es/m/20200205172259.GW3195@tamriel.snowman.net

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/dcddc3f813ff39d0e33c2b7c77092a6c0b0e9d0b

Modified Files
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src/bin/pg_basebackup/pg_basebackup.c | 16 ----------------
1 file changed, 16 deletions(-)