i2c: acpi: export i2c_acpi_find_adapter_by_handle

This allows drivers to lookup i2c adapters on ACPI based systems similar to
of_get_i2c_adapter_by_node() with DT based systems.

Signed-off-by: Ruslan Babayev <ruslan@babayev.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>