pgsql: Fix inappropriate error messages for Hot Standby misconfiguratio

Fix inappropriate error messages for Hot Standby misconfiguration errors.

Give the correct name of the GUC parameter being complained of.
Also, emit a more suitable SQLSTATE (INVALID_PARAMETER_VALUE,
not the default INTERNAL_ERROR).

Gurjeet Singh, errcode adjustment by me

Branch
------
master

Details
-------
http://git.postgresql.org/pg/commitdiff/2e0cc1f031387fc304d11e55df0f9566d91698ff

Modified Files
--------------
src/backend/access/transam/xlog.c | 9 +++++----
1 files changed, 5 insertions(+), 4 deletions(-)