Merge branch 'PHP-7.4'

* PHP-7.4:
  Add support for Interbase 1 dialect

diff --cc ext/pdo_firebird/firebird_driver.c
Simple merge

diff --cc ext/pdo_firebird/firebird_statement.c
Simple merge

diff --cc ext/pdo_firebird/php_pdo_firebird_int.h
Simple merge