ACPI: EC: Avoid printing confusing messages in acpi_ec_setup()

It doesn't really make sense to pass ec->handle of the ECDT EC to
acpi_handle_info(), because it is set to ACPI_ROOT_OBJECT in
acpi_ec_ecdt_probe(), so rework acpi_ec_setup() to avoid using
acpi_handle_info() for printing messages.

First, notice that the "Used as first EC" message is not really
useful, because it is immediately followed by a more meaningful one
from either acpi_ec_ecdt_probe() or acpi_ec_dsdt_probe() (the latter
also includes the EC object path), so drop it altogether.

Second, use pr_info() for printing the EC configuration information.

While at it, make the code in question avoid printing invalid GPE or
IRQ numbers and make it print the GPE/IRQ information only when the
driver is ready to handle events.

Fixes: 72c77b7e ("ACPI / EC: Cleanup first_ec/boot_ec code")
Fixes: 406857f7 ("ACPI: EC: add support for hardware-reduced systems")
Cc: 5.5+ <stable@vger.kernel.org> # 5.5+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>