pgsql: Avoid non-POSIX cp flags

Avoid non-POSIX cp flags

Commit 252dcb32 used cp -a, but apparently Solaris doesn't like that. Use cp
-RPp instead.

Author: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: /messages/by-id/CA+hUKGL10AoQVMMqgOJ8CTjoz9MLidD8ik2e8PibzLNMz0+aRg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1a4fd77db85abac63e178506335aee74625f6499

Modified Files
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src/test/perl/PostgreSQL/Test/Cluster.pm | 2 +-
src/test/regress/pg_regress.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)